SUCCESS - TWO OUT OF THREE (RUNNING OSX 10.8) AINT' BAD

The hardware part of this mod has already been completed, for the most part.  The next step is software and finding a build that will run Mountain Lion without much compromise, is the goal.  Out of the 4 boards I am working with, I have had tremendous success with one, partial success with another, hit a dead end with a 3rd, and the 4th is somewhat of a backburner side project (upgrading my previous sandy bridge mod to core i7 Quad and Mountain Lion).

 

Lets start with Success: THE EPI-QM77

THE BUILD

This is the EPIC board, it is slightly larger than the ECX board, but fits easily within the dome.  As always this is a purchased retail copy of Mountain Lion using the brilliant tonymac's Unibeast/Multibeast install method (Thank you again tonymac).  Changing the SATA from IDE to AHCI was the only change I had to make in the bios, otherwise it installed natively.  Interestingly, I had trouble getting the USB to function from a USB 3.0 port, but when I plugged it into the apple keyboard's USB via the USB 3.0 it worked fine.

An Ivy Bridge "MacBook Pro" in an iMac G4 shell

I am still tweaking the multibeast settings somewhat, but will report them with final recommendations shortly.  As you can see, this build eschews the optical drive for the native PSU.  Although this is cleaner as there is no power brick, I have mixed feelings about loosing the aesthetics of the drive.  Its getting harder to justify what is really a cosmetic feature at this point.  I am still trying to devise a use for this and to somehow incorporate a usb powered motor to open and close the door revealing a hot plug or extra ports.

I will have to see what might be needed from a cooling perspective, but I may need to upgrade to a larger heatsink, but can not be sure until the computer is fully assembled.

This is likely the build I will keep as this board has everything I need, Core i7 Quad Ivy Bridge with HD4000 graphics, Enough USB 3.0 slots and 2 SATA 6.0 ports.  Even a quality 7.1 Realtek Audio Chip is included.

 

The "Looks Promising" Board: THE INTEL DC3217BY

Rear ports

On tonymac's forums I have seen successful hackintosh builds using the sister model which has ethernet and two monitor support.  This is the "higher end" model because of the inclusion of a thunderbolt port.  With the help of mikeboss' tip to set the graphics to 128mb, this board was able to post.  I did not go further as a mSATA is required and I did not have one large enough until now.  I have installed this Crucial 128GB mSATA, as well as a broadcom half height wifi card.  As this board is nearly identical, I suspect I will have similar success.  The question will be the thunderbolt, which I am hopeful will work natively.

With RAM, Wifi, and mSATA installed

I doubt this board will end up in this build permanently, but its an important proof of concept.  I believe that this tiny form factor has potential and Intel is currently pushing it for hobbyists.  Hopefully they will continue to improve and expand this line.  However, this first generation is underpowered with a core i3 vs the other boards.  Also it has few ports.  While the thunderbolt is intriguing and the idea of having all the ports in the back connect to one thunderbolt internally (ethernet, extra display, usb's etc) similar to apple's cinema display, thunderbolt accessories are currently way overpriced.  This board, as its the most compact, is the most versatile and is likely to have many uses in other projects.  That said, nothing is certain, and I will see this through.

 

NOT AT ALL: The Gene HM-76

I had high hopes for this ECX board, but I am currently having issues with the DVI display.  I am unsure if this is a failure of the board or its ability to communicate with my DVI/TMDS mod.  There are a few things I still want to try. 

 

WAITING IN THE WINGS: THE KEEX-6100

As Lion ran so well on it, I doubt Mountain Lion will be a problem, but I will test this as well as the core i7 processor.

OTHER OPTIONS:

A New QM-77 Ivy Bridge Board:

Quanmax will be releasing the Ivy Bridge KEEX-7100 and 7101 which contain embedded Core i5 and Core i7 mobile processors respectively.  ALthough I have a fondness for Quanmax and its KEEX boards have served me well, this board is not yet available and this is somewhat late in the game.  As I frequently change processors and tinker, I try to avoid embedded systems if possible (no other option with Intel NUC, but price is actually reasonable for a processor included system), but it remains a viable alternative.  

The Old Mac Mini:

I have been looking at ebay and the white polycarbonate Core 2 Duo systems are falling in price.  While the new boards are too big, the older style will work, but price to performance has been a limitation.  Although underpowered, there is a huge advantage in a native OS X machine and the final iterations (2.5+ Ghz) are still capable machines.  I will have to see if I can obtain one at a reasonable price.

Thanks for reading, will keep updating as I go.

17" iMac G4 (1/1.25Ghz Neck) Video Tutorial

What you see here can be applied to the other iMac G4's, just use the correct pinout.  This is the first time I have ever done a mod in front of the camera and this was more difficult than I anticipated.  This was done live in real time (for the most part).  I sped through the portions that were simply repetition (such as stripping a wire or pushing out every last pin) and did cut very small portions (mostly because I felt I said or did something confusing).  I do apologize for frequently pulling out of the shot, its hard to work on a small item with a camera in-between you and the project itself.  I still believe this is useful to people who are better at visualizing than pinouts or snapshots.  Also, you can get a sense for the time this takes.  While soldering and stripping can take days, without the camera and explanation, I could have finished this in an hour.

There are a few highlights:

-  To make the extra wires I used the iMac's own ground pins.  This worked great and saves you having to buy an extra neck.  This is certainly the way I would recommend proceeding at this point.

-  Frustratingly, I have purchased a refurbished 17" 1ghz neck to use in this demonstration (as I did not have any more completely intact ones).  It did have some variation in that in the black lcd cable, one of the four wires in the black cable, the Red Wire was replaced with a Gray/Off White wire.  In addition all the the positive TMDS wires that emerge from the four wires that are usually Red, were also Gray/Off-White.  I have seem a random color variation in refurbished necks before, however, it was frustrating that for my demo, this one had more variation than I have seen before.  So just remember, for the black LCD cable Gray = Red.  And also be aware that this variation does exist.

- The final part that involves connecting the Red Inverter Wire to the VEDID/Pin 14 is very important because of the way we have it setup.  The inverter will not turn on appropriately unless this step is done.

-  When making the extra cables from the 3 ground wires with pins in the iMac's Gray Cable, I add one extra wire (a black wire I took and stripped from the iMac's fan cable).  The wire is not really necessary, you can hook the resistor directly to the other wires, but I feel that one extra wire not only makes it more secure, but also gives an extra area when we split again by adding the Red Invereter Cable.  Remember this actually becomes a 3 - way split with 1 split going to the LCD via the iMac's own Red/Hot Pink wire, 1 split going to a resistor then back to the DVI via Pin 16, the hot plug detect, and the final split going to the Red inverter wire.  So the extra wire allows us to kind of split once, then split again, as opposed to a direct 3 way split.

This has also been integrated into the blog, but here are all 9 parts together:


Part 1: Introduction and Parts List

Part 2: Completion of the Parts List

Part 3: Freeing the Inverter Wires

Part 4: Freeing the LCD Wires

Part 5: Hooking up and Testing the Inverter

Part 6: Connecting the Black LCD cable

Part 7: Powering the Gray LCD Cable

Part 8: Hooking up the Gray LCD Cable

Part 9: Finalizing the Inverter and Demonstration

Hope this helps and good luck.  Thanks for reading and watching!

iMac G4 Mod Advice

I hope this doesn't come across as preachy, but I just want to give some advice to those of you new to modding the iMac G4.  I have disassembled and reassembled this computer so many times I could probably do it blindfolded.  There are a few aspects of modding this computer that have led to a lot of frustration for me, a few pointers, hopefully, will help some of you.

1) If your goal is to connect your iMac G4's LCD to modern hardware.  Use the Native LCD with the "TMDS to DVI Method".  Changing all the wires to some other method of connection such as LVDS is very time consuming, less stable, and more expensive.  There is no reason not to use the native TMDS wires that go from the native LCD through the neck.  Apple has already done the work for you! Plus, TMDS is a digital signal that is more stable over distance than LVDS and TTL.  Apple has put the controller inside the LCD itself, with other LCDs, you would have to add one.  I have done this both ways, replacing the screen and replacing/soldering the wires takes hours and likely days.  By using the TMDS to DVI Method with the DVI Connector below, you could get a signal within 30 minutes that is superior in every way.  Which brings me to.....

DVI Connector

2) USE THIS DVI CONNECTOR!!!  (MOLEX PN 74320-4004 - though other variations which work just as well exist).  It is very cheap and makes this mod so much easier.  I can not emphasize this enough. I know a male HDMI may be more convenient (or even a male DVI), but for the price of an adapter you will save yourself a lot of frustration.  Sure you could cut off an HDMI cable and solder it to the iMac G4's pins, but this is a much harder task than you may think.  The TMDS channel wires in the Black LCD cable are as thin as a hair and this is no exaggeration.  If you manage to spare the pins at the end of the wires during soldering this can be done.  But, as the pins are soldered to the ends of the wires themselves, they have an annoying habit of falling off when heat from a soldering iron is applied.  Also, if you make a mistake while soldering there is no going back.  As this is a digital signal, one broken connection can mean no signal at all.  What's more is that even if you do things perfectly, you can still have signal problems.  One mod that I made I had to cut and reconnect again (so I lost all the pins).  Despite a perfect connection, the image was plagued by artifact.  Another time, I had red/green pixels "dancing around" when viewing certain colors.  I ended up having to replace the entire Black LCD cable (with the TMDS signaling cable from an Apple Cinema Display which has thicker wires) to solve the problem.  TMDS uses minute differences between the positive and negative wires (and their shield wire) to communicate.  Altered resistance in the form of a little too much solder or too much wire wrapped around can result in these types of artifacts even if you are extremely good with soldering.  This DVI connector makes this almost plug and play.  The pins fit perfectly,  you don't need to solder at all.  I am not exaggerating when I say that this method saved me 10+ hours of intensive work on my recent mod.  Besides having to put a piece or two of electrical tape over some pins to prevent cross-talk, my image has been pristine every time I have used this connector.  Do not repeat the same mistakes that I have made.

iMac G4 Neck with Cinema Display Wires

3) Although no longer necessary with the TMDS to DVI Mod, if you want to add or change some wires, do not be scared to open the neck.  Its not hard, does not require special tools, and is not really dangerous.  I have written on this blog about the exploding neck because I had read about it myself.  I've had an open neck fall off the table, I've left necks open for weeks at a time, and have never had the spring fly off.  I wouldn't throw an open neck as hard of you can against the wall, but you do not have to handle it like its plutonium.  Just keep in mind that  if you do knock the spring off its moorings it takes a lot of work to pry it back up into position.

4) If you need to add wires to the neck, do not put more/thicker wires into the neck than it can hold.  Just because you can get it through the holes does not make it a good idea.  When you overcrowd the neck, you'll start to hear grinding and some wires will wear down as they are pushed into the hinges of the neck.  The iMac G4 has 4 wires that go through the native neck.  When you replace wires, take out what you're not using and aim to have about the same "volume of wires" as the native neck comes with.

5) Get rid of the Torx-6 screws.  These are the most troublesome screws I have ever worked with.  On the bottom of the 17" and 20" iMac G4's monitor housing you will find 3 screws that require a Torx-6  screwdriver to open.  These are the screws that keep the monitor housing closed.  I have never seen screws that strip easier despite using the appropriate tool.  6 points on a tiny screw is very close to a circle and once you start stripping it - its already too late.  Chances are good that you may have to open up the monitor housing again at some point for upgrades, repairs etc.  Act preemptively and replace these with small phillips screws - it will save problems later.

5) Want an All-In-One? Consider an 3.5" ECX or other small form factor board.  Although mini-itx or a mac mini motherboard are the most popular choices neither of these is ideal from a size/heat perspective.  ECX's can fit at the top of the dome in place of the native HDD where heat won't be as big a problem as it would with a mini itx at the bottom of the dome.  They don't require an atx power supply and come with a variety of additional options including PCI-E mini or x4, Compact Flash etc.  Processors range from Atom to AMD Fusion to Sandy Bridge Core i processors.  This allows you to keep the full 5.25" drive if you want and allows room at the bottom of the dome for ports at the back.  Although not nearly as expandable as a mini-itx mobo, with such limited space in the dome, this isn't likely to matter.

6) Do not sacrifice stability for power.  The mods I've posted usually don't include the mods which failed.  Most of these initially worked but failed because I tried to force things.  If you have to use all your strength to push your mod closed to screw it in, it will not last.  If you cram things in between the motherboard and the air holes, your board will overheat.  Keep expectations in check.  If you have a 17" monitor running at 1440x900 you don't need SLI or Crossfire.  Having it turn on and having a critical problem like this is worse than it not working at all.  If it does not turn on, you can start troubleshooting what went wrong.  These problems (like my 20" TMDS to LVDS with too many wires through the neck) usually require a complete redesign and many of the parts have to be repurposed or replaced altogether.

Hope this helps.

Afterthoughts and Future Plans

20" iMac G4 and 20" iMac G5 (Apple Cinema Display LCD Controller Hack)
Connected  to External Mac Mini

Genuine 20" iMac G4 All-In-One Sandy Bridge Hackintosh

Above you see my two favorite 20" mods.  The one on top uses an LCD controller from an Apple Cinema Display for both the iMac G4 (though the iMac G4 uses its native inverter) and the iMac G5.  These are connected to an external Mac Mini.  Although somewhat more complex, the great thing about this method is its stability.  It is really an apple cinema display in the form of an iMac G4 and G5.  The extra room in the in the iMacs is not put to waste.  The iMac G4 houses a USB optical drive (replacing the missing one on the Mac Mini.  The iMac G5's iSight and Mic are converted to USB.  This has become one of my most frequently used computers.

The second picture is my latest All-In-One Sandy Bridge Hackinosh using an ECX board to run Mac OS Lion.  This is very much native and did not require any alteration to the neck or lcd.  The computer, DVD burner, SSD (running lion) and onboard Compact Flash (running Windows 8 Developer Preview) are all internal.  This was a tremendous amount of fun and will make a great all-in-one computer.

Obviously both these methods are viable and both have their advantages.  From the outside, they are indistinguishable from each other or a native iMac G4.  Of course, which ever method you use for the LCD is independent of what you connect it to.

iMac neck connected to Apple Cinema Display

My slightly older 3rd method, used the actual housing from an apple cinema display.  The few extra millimeters this gave allowed the use of the cinema displays inverter (I had previously not been able to get the 20" iMac's native inverter to work).  This method also allowed for the addition of a 20" touch screen.  However, I have retired this mod for a couple reasons.  First, while I thought this was an acceptable work around at the time, I much prefer the look of the true LCD housing.  Second, while the touch screen was great with the iMac's design, I did not love the only touch screen I was able to find in the now rare 20" 16:10 size.  This resistive touch screen was fairly accurate, but its surface was uncomfortable to touch and its glossy plastic surface detracted from the resolution of the LCD.  Third, as a resistive screen single touch was all it could do.

While I now have a functional upgraded replica, I still like the idea of adding additional functionality to the iMac G4 with a touch screen.  There are a couple options that are now available.  Some capacitive screens have become much more reasonably priced.  Although they were originally designed as single touch, new software may be able to make them function with gestures and at multitouch.  Another possibility is optical or IR touch.  Although the available optionals do not come in 20" 16:10, they possibly can be tweaked.

The downside is that the 20" capacitive screen will add too much weight and the optical touch will require extra room between the LCD and the bezel.  One thing that may make this possible is to use LED backlighting which would be much thinner.  A fellow modder JP7 has done a fe amazing mods of apple cinema displays using LED backlights.

In terms of the base, I have no use for either a desktop monitor or an all-in-one.  But, a larger screen for a notebook computer has always been something I have considered for the iMac G4.  Using either wired technology (A thunderbolt dock? - If they eventually come in at a reasonable price) or wireless technology (Wireless DVI and USB adapter?) is something I can definitely see being useful.

Wireless DVI - Courtesy of Amazon.com

After I use my current G4 and G5 spare parts, I will probably move on from this.  And I still have a Cube which has been sitting waiting to be modded.

Advice to Modders

I hope this doesn't come across as preachy, but I just want to give some advice to those of you new to modding the iMac G4.  I have disassembled and reassembled this computer so many times I could probably do it blindfolded.  There are a few aspects of modding this computer that have led to a lot of frustration for me, a few pointers, hopefully, will help some of you.

iMac G4 Neck with Cinema Display Wires

1) Do not be scared to open the neck.  Its not hard, does not require special tools, and is not really dangerous.  I have written on this blog about the exploding neck because I had read about it myself.  I have knocked the spring off its moorings numerous times and that just means a lot of work to pry it back up into position.  I've had an open neck fall off the table, I've left necks open for weeks at a time, and have never had the spiring fly off.  I wouldn't throw an open neck as hard of you can against the wall, but you also do not have to handle it like its plutonium.

2) Do not put more/thicker wires into the neck than it can hold.  Just because you can get it through the holes does not make it a good idea.  When you overcrowd the neck, you'll start to hear grinding and some wires will wear down as they are pushed into the hinges of the neck.  The iMac G4 has 4 wires that go through the native neck.  When you replace wires, take out what you're not using and aim to have about the same "volume of wires" as the native neck comes with.  To get wires through the neck all you have to do is push a wire that is already through backwards and  tape about 1/2 an inch of the wire you want to get through to that wire and pull it through.

3) When you can't get a signal replace the black wire.  I have heard from many people who can not get the 17" DVI hack to work.  I know what the problem is - its the black wire.  If one wire isn't touching then there is no signal.  Too much solder on these wires causes problems.  Even if you get a strong signal on the mutimeter, crosstalk can result in color changes, flickering image, etc.  The wires are simply too small to reliably work with.  Give it a shot and try to spare the pins that are attached.  But, if you need to - replace them.  Replace them with what you may ask.  I used an apple cinema display's wiring here, but these are no different than any TMDS cables and the easiest place to get TMDS cables - take a DVI cable and strip it.  You will find 4 wires that have three wires bundled within them, these are the same as the 4 wires within the iMac's black wire.  Solder the pins to the top and you're set.  Even though it will be four wires to one, they are thinner and if you need remove the led/microphone wire go ahead and do it.  For my current mod, I have repaired problems with the black cable numerous times, I finally decided to replace it, with the apple cinema display's wires and haven't had a problem since.

4) Get rid of the Torx-6 screws.  These are the most troublesome screws I have ever worked with.  On the bottom of the 17" and 20" iMac G4's monitor housing you will find 3 screws that require a Torx-6  screwdriver to open.  These are the screws that keep the monitor housing closed.  I have never seen screws that strip easier despite using the appropriate tool.  6 points on a tiny screw is very close to a circle and once you start stripping it - its already too late.  Chances are good that you may have to open up the monitor housing again at some point for upgrades, repairs etc.  Act preemptively and replace these with small phillips screws - it will save problems later.

5) Want an All-In-One? Consider an 3.5" ECX or other small form factor board.  Although mini-itx or a mac mini motherboard are the most popular choices neither of these is ideal from a size/heat perspective.  ECX's can fit at the top of the dome in place of the native HDD where heat won't be as big a problem as it would with a mini itx at the bottom of the dome.  They don't require an atx power supply and come with a variety of additional options including PCI-E mini or x4, Compact Flash etc.  Processors range from Atom to ULV Celeron to Sandy Bridge Core i processors.  This allows you to keep the full drive if you want and allows room at the bottom of the dome for ports at the back.  Although not nearly as expandable as a mini-itx mobo, with such limited space in the dome, this isn't likely to matter.

6) Do not sacrifice stability for power.  The mods I post don't include many mods which failed.  Most of these initially worked but failed because I tried to force things.  If you have to use all your strength to push your mod closed to screw it in, it will not last.  If you cram things in between the motherboard and the air holes, your board will overheat.  One mod I did post that was going to fail was the 20" TMDS to LVDS Conversion.  Keep expectations in check.  If you have a 17" monitor running at 1440x900 you don't need SLI or Crossfire.  Having it turn on and having a critical problem like this is worse than it not working at all.  If it doesn't work you can at least start troubleshooting what went wrong, these problems like the 20" TMDS to LVDS usually mean complete redesign and many of the parts have to be repurposed or replaced altogether.

Hope this helps.

Update - The Native Inverter and LCD Glass

First let me start off by saying that I did something very stupid despite me writing not to do this time and time again.  I soldered the DVI connector on without putting it through the hole in the dome.  So I had to cut and resolder and for those of you that have never seen the components of the black wire of the imac neck, I can tell you it as an absolute nightmare.  They are composed of 4 wires in which are 3 wires; a red (+), a green (-), and a ground.  The red and green wires have a small plastic coat surrounding a single wire that is the size of a hair. When I set up this initially I had the bottom pins on and was able to use a tiny dab of solder, having to resolder these tiny wires, wire to wire has caused signal problems.  Keep in mind even one failed connection will give you no image whatsoever, so a multimeter is very helpful.  But poor connections or poorly shielded connections will result in color distortion.

That said there is some very GOOD news.  The native LCD for the Apple cinema display (LM201W03) needs to be modified to fit and although it fits, I decided to try the native iMac G4's (IDTech 20.1") lcd glass and it also appeared to work (though until I have a perfect image I can not confirm this 100%).  So it is possible that the only thing you may need is the LCD controller board from the apple cinema display and the cable to get this mod to work as the native G4 inverter has been confirmed to work and the native LCD glass appears to work.  This would be quite helpful as you can use a broken cinema display with a cracked screen.

 To the right you see the mod to date.  The top monitor housing closes as easily as the original as it uses the native inverter and the native glass.  Because I wanted this mod to be as close to the original as possible - I actually purchased a new monitor housing and base cover from ebay as most of the broken used iMacs I have acquired tend to be yellowed or scratched.

You can see the monitor from the front, side and back.  To the right of that is the lcd controller and ECX motherboard.  The ECX boots from a compact flash card located on the underside of the board.

The ECX board is the size of a 3.5" drive.  My plan is to mount the ECX board on top of a blu ray drive in the native drive caddy.  (essentially taking the place of the native hard drive).  As the CPU fan will be sitting at the top of the dome, I will not need a fan, so I should be able to fit Wifi and Bluetooth at the top of the dome with the vent holes.  As I will not be using the native power supply I should have room around the ECX board to fit connectors.  The lcd controller board will replace the native iMac G4's motherboard at the bottom of the dome below the drive.  As its smaller than the native motherboard I'm hoping to have room to wire up some rear I/O ports.  The only downside is that this leaves no room from the power supplies for both the monitor and ECX board.  They would fit in the drive caddy and using a splitter a simple AC plug could be placed in the back, but then obviously there would be no drive.  I have thought about using the native iMac's power supply, but I really need the room and in a similar experiment I fried a different ECX board in the past.

So, I'm going to keep them external.  For one the power supplies are small and this is a desktop computer, it won't be moved that much.  Plus, I have always loved the drive and by using blu-ray it can be useful.  Also, its gonna be tight in there and there is really no cooling system in place - so keeping hot power sources external is probably for the best.

I do think the system is likely to be hackintoshable - the chipset has been hackintoshed before (this is the Quanmax KEEX-4030 ECX board for those interested).  The thing that I have never heard about is booting snow leopard from a compact flash card - a 2.5" or even 1.8" SSD may have to be shoehorned in somewhere if hackintosh is your goal.

Here is the system booting (again notice the small resolution during the boot that I previously discussed).

This is where the frustration set in - with windows booting.  While I previously had a pristine image, after the resolder, the colors are unfortunately off.  A multimeter revealed all intact connections but I was getting some week noise at the wrong pins - so I suspect some interference or crosstalk.  I'm going to remove all the solder joints for the black wires and try redoing them with fresh connections and extra shielding.

To do this mod, I actually used cables from the necks of different iMacs.  There are the black and grey cables that carry the DVI signal, however the apple cinema display has "extra wires".  Some of these probably aren't necessary, but some of them are.  As a result, I had to add an extra grey wire from a different iMac.  I replaced the native LED/Microphone cable with this wire.  The wiring is somewhat difficult to explain.  If I continue to have difficulty with the black wire of the native iMac, I will likely change it to a different wire.  Likely either the equivalent wires from the apple cinema display or another grey wire.  Both of these choices would be MUCH easier to work with.  Either way when I do finalize how I wire the neck, I will post specific instructions.

While I am quite proud of some of the previous mods - this mod is actually much simpler and besides having to push some wires through the neck, a lot less labor intensive than previous mods.  In addition, if it does turn out, as it seems, that either LCD panel can be used, combinations of discarded iMac G4's and apple cinema displays can be used.  I would NEVER tear apart a working iMac G4 and couldn't bring myself to tear open my mac mini to try to fit it in the base.  I even hated even using a working apple cinema display in my previous mod.  Its always great to re-purpose otherwise useless parts.  But whats great about this mod is that there are so many different ways, but this one feels the closest to the native 20" iMac G4 that I've come so far.

Keep in mind that the KEEX-4030 uses the same Socket P Penryn Core 2 Duo chip thats in the previous and current generations of minis.  This ECX board is no slouch.  That said, if there was a problem with it, I think this is the mod that I would open up a mac mini for and try to put it in the base.

I'm hoping to figure out the wiring, clean up the image and start putting the base together this weekend.  But, as always all comments and suggestions are appreciated, but please no comments about seeing windows on the iMac G4 - Its the only operating system I currently have on a compact flash card.  Also feel free to ask any questions.

iMac G4/Cinema Display Mod - Improvements

So far this mod is as close to perfect as I have gotten, but there are a few things that I felt could be improved.  For one - with the touchscreen and iMac bezel in place there is a one area where I was getting "monitor drift" that is the neck would slip down an extra inch or two when positioned in a certain way.  Secondly I did not love that the touchscreen is located in front of the cinema displays bezel or that it was held on by mounting tape.  Thirdly, despite doing a better job hiding the touchscreen wire, I still found it somewhat unsightly.

My initial intention was to make the touchscreen easily removable, but having used this mod with the touchscreen, I would never remove it.  So I decided to integrate it into the display.  However, the 5wire resistive touchscreen although only a few mm thick will not fit under the bezel.

I looked for film to film touchscreens but could only find them in 18.5" or 21.5".  Plus chances are its not a 5wire.  I know everyone wants capacitive, but 5wire resistive is very durable and for the price, very reasonable.  For those interested the screen I use:

http://cgi.ebay.com/20-1-5-Wire-Resistive-Touch-Screen-Panel-Kit-USB-16-10-/270694746748?pt=LH_DefaultDomain_0&hash=item3f06aa0a7c#ht_6098wt_1235

The company ships fast and it packages it very safely in a plexiglass lined box.  So here is how to integrate the touchscreen.  Again this is only for people that are using this particular touchscreen.

To start I wanted to decrease the weight a little bit to compensate for the touch screen.  I decided to remove the top portion of the bracket.  Although this gives less surface area for the glue to hold.  The weight is actually supported by the aluminum frame itself - so this part protects from rotation more than anything.  I used cold weld epoxy and am confident that even without the top of the bracket its not going anywhere.  But I still had to figure a way to mount the touchscreen flush against the lcd.

So to solve this I actually cut out part of the front bezel of the apple cinema display.  I positioned the touchscreen in the center, traced around the screen and dremeled that area out.  This allowed me to put the touchscreen flush against the lcd screen and the monitor is still securely held by the remaining bezel.  The touchscreen is also firmly held in place by the square cut for it.

Previous Method

New Method

To the left you can see the difference.   The new bezel is pictured on the bottom.  You can see the front is much thinner as well as having the smaller bracket.

The original method is on top.  Again, unless you are planning on using a touchscreen and it is similar to this one, I would recommend using the original method.

One complication of this is that the Cinema Displays LED indicator gets cut off.  This gave me the opportunity, however, to use the native iMac G4s LED.  As they use different 2 pin connectors of opposite sex, I had to create a hybrid using the LED wires.  I can then plug the LED wires coming from the Apple Cinema Display's Control Board into the ribbon LED from the native iMac G4.  The ribbon cable easily fits between the touchscreen and the bezel.

Hybrid LED cable

iMac G4 Bezel with LED

I then used tape for two reasons.  One, I wanted to make sure the touchscreen doesn't fall forwards (even though its wedged in there very snugly).  And secondly, I wanted to give an area where I could put an epoxy to adhere to the iMac G4s front bezel (without gluing directly to the touch screen), which becomes the new front, replacing the Apple Cinema Displays front which was largely dremeled out.

Touch Screen flush with bezel

The touchscreen ribbon cable now goes internally and thus no cables are visible.  It connects to its 5 pin adapter and goes down the neck to meet the controller in the base. Its difficult to see in this picture, but the touchscreen is now flush with the remaining part of the Apple Cinema Displays front bezel.  Using epoxy the iMacs bezel was attached, sealing off our now heavily modified hybrid case.  The case still opens and closes like the original Apple Cinema Display, but now the touchscreen and iMac bezel are fully integrated.

The best way to see the difference is from the side.  Previously you had Apple Cinema Display with a few mm of touchscreen visible in front then the iMac bezel.  Now the new bezel interacts directly with the original case.  Plus, there is now no visible wire anywhere as everything is internal.

In addition, there is no "monitor drift" - NONE!! Not in any position.  If this is the effect of some weight removal or simply moving the touchscreen inwards a few millimeters - I can't be sure.   But, either way it worked.

As an added benefit the iMac G4s native LED looks great.  Sometimes the little things really do go a long way.

The only negative is that the touch screen is no longer "easily removable".  I decided that really the only use I have for a 20.1" 16:10 touch screen is for this mod.  Plus, after a few days it became clear that this mod is even better with the touch screen (in my opinion) and that I wasn't going to opt to remove it.  I will be posting a full parts list and step by step for this mod.  I will do my best to separate it into with and without touchscreen.

As a side note, you may notice some of these pictures use the apple cinema display that I had painted white.  After looking at the white version, I decided to stick with the original silver of the apple cinema display.  For one, I am not the best painter and it had already chipped in places.  Secondly, the silver really goes and it matches well with apples keyboard/mouse and even the mac mini.  Although using the original display would be ideal, I feel this has some advantages.  The presence of USB (and firewire if you wanted to hook it up), on/off switch, brightness control, more mod friendly (room for longer cables etc.).  As always, questions, critiques etc are welcomed.

Pressing the Cinema Display's Power Button

20" iMac G4 Mod - TMDS to LVDS (Not Recommended)

UPDATED (11/5/11): I have condensed all the posts that involve this mod to this post for better organization.  Again this method is unstable and potentially dangerous.


This method is no longer recommended as I have since found much better, cheaper, and safer. ways of doing this. there is a safety issue and I do not want to see anyone get hurt.  I am tempted to take this post down but I do believe there is value for people that want to convert from TMDS to LVDS.  The dangerous part of this is the inverter wires.  As I placed the inverter in the base I lengthened the wires that connect from inverter to backlights.  Once the current passes through the inverter it becomes very high voltage.  The 20" version has 6 backlights when you add these cables (12) to the LVDS cables - you have to run more wires through the neck than it can really hold.   What this results in is wires that are rubbing against the hinges of the neck.  I started hearing an electrical humming sound and became concerned enough to disassemble this mod.  Recently I decided to open the neck apart to salvage some wires for parts.  I saw clear evidence of wear to the shielding of the wires.  If the shielding wears on the inverter wire it could easily arc to the metal neck and electrocute anyone who touches it.  Here is a video someone has made demonstrating the ability of the high voltage in the inverter to backlight cable to arc.
Inverter CCFL video

Original Post:

Completed LVDS 20" iMac G4

I. Overview

The biggest question is if you want to use the original monitor which uses TMDS signaling or replace the monitor with one that uses the more standard LVDS. I decided to replace the panel with a standard LVDS panel.

The next decision is size, I decided to go with the 20 inch iMac here. Some people prefer the 17 inch model, but its all personal preference. As long as you are careful about monitor choice this mod is actually easier on the the 17 inch model. Remember to choose a panel that is 16:10 not 16:9.

I ended up going for the LG 204WT. Its a good monitor, has the right aspect ratio, and because I burnt out my last one, I had spare parts. I ended up finding a refurbished one for $90 on ebay. This monitor has some other nice features for the mod. It has a small keypad (the power and menu buttons), it uses an LVDS wired cable, not a ribbon cable, and the power source can fit into the base. Because the base has four brackets that come down around the DVD drive, you can use this as a guide to see what will and will not fit. So if its bigger than a 5.25 Drive its prob not going to fit.

Another decision is to make this an all in one or not. Because the power source and inverter need to be in the base there is little left over room for any computer components.

There are instructions on how to take apart the iMac G4 online and I won't go into specifics but to say you need to seperate the neck from the monitor and base. Almost everything in the base will not be used for this modification. Most of this mod revolves around the neck. To take apart the neck I used a mini screwdriver set and taped two together. You may need two sets and someone to hold the other side of the bolt steady while you turn initially. The neck is not difficult to take apart. This is shown below:

Tape 2 together for 2 sets

II. Wiring
Again, Do not wire the inverter to CCFL through the neck.  It is OK to keep an inverter in the monitor housing and lengthen the cable to the inverter.  But, I can no longer recommend lengthening the wire from the inverter to the CCFL backlights through the metal neck as this is a high voltage wire and there is risk of this arcing to the neck and electrocuting anyone touching it when this happens.


Remove all of the iMacs native wires.

You should first put through the inverter extensions as they are the thickest wires.
The small two pin inverter connector can fit through the neck and does not need to be removed.

There are 6 CCFL backlights (each with a high and low voltage line). The 4 pin cables support 2 CCFL lights and the 2 pin cables support one in the 20 inch monitor. For the high voltage lines, I decided to use heavy shielded inverter extension cables. These wires are very high voltage and high voltage can arc if exposed. The last thing you want is an exposed wire arcing in a metal neck. It can be VERY dangerous. I bought 6 inverter cables from an HP Omnibook on Ebay. They are 15" It takes two extension cables that link in the neck to make it all the way through..

If you decide to use an LVDS panel, you should replace all of the wiring in the neck. LVDS uses a series of paired wires (for the most part). Most LVDS cables have a 30 pin connector of which usually 27 wires are used. In addition, you have to lengthen the inverter wires, that is two wires each for the two inverters. You also have to lengthen the low voltage lines for the inverter as well. As you can see that makes a total of 39 wires that have to go through the neck. Things will get VERY crowded in there.

Remember to be cautious with an open neck, the spring can be dangerous. As long as the neck is open you should tape it down.

For the LVDS cable, you can either order an LVDS cable online or you can make your own. You can use 30 gauge kynar wire. Because I had several LVDS cables from previous mods, I decided to use these. I ran 27 70cm LVDS wires through the neck. The advantage to using LVDS cable is that they already have the pins on them, which makes soldering easier. You have to remove all the pins from the connectors, you can only fit wires through the neck, connectors will not fit. (Except for small inverter connectors). As you run the cables in make sure you label them on EACH END. You will need to know what to solder where.

For the low voltage inverter cables I chose CAT5 wire, I simply cut apart an ethernet cable, stripped it and ran the wires through the neck.

 

With the LVDS wires through

III. Soldering
With the 27 LVDS wires, the 8 + 4 inverter wires through, you can close up the neck in can be difficult to close and you may need to use your screwdriver as leverage. You should try to add shielding to as much of the wiring as possible. However, this is difficult as there are so many wires.

Soldering the LVDS cables

I ran the 27 LVDS wires through the neck, however they need to be extended at both ends and end in connectors. I soldered the top (monitor part) to another 50cm LVDS wire and then the bottom to the existing LVDS cable that came with the monitor. If you do not have extra LVDS cables. I'd recommend simply running 120cm of Kynar wire through the neck, then cutting the existing LVDS cable in half and soldering each wire to its appropriate match at each end. Remember to label all the wires.

I also decided to cut off the 4 pin inverter connectors from the native iMac G4 panel and the native inverter (I did not want to have to cut the wires on the LG panel to attach. I then attached these connectors to the the inverter cables. Pink cables are high voltage, white cables are low voltage.

Soldering the inverter attachments

This is a good place to check the connection. Disassemble the monitor to expose both LCD controller board and the inverter and power source.

First I tested the connection.

Then I added the inverter cables.

 In both tests there was a clear image that ran through the neck. Now that we know it works, we can assemble the base.

IV. The Base


Run the wires through the base and screw in the neck. Connect the wires to the LCD controller and place it at the top of the dome.

Then connect the inverter cables to the inverter and power source. Use screw to attach the power source to the dome.


For the drive, you have to modify the cady, cut the top off (where the hard drive would normally sit). Leave only the side rails and attach them to the drive then screw in the drive. This way the monitor components are protected at the top of the dome.

Wires at Top of Dome

LCD Controller Installed

Power Board Installed

Ready for LCD

You will need to tape the wires flat against the back so you can close the monitor eventually. Its not pretty, but it works.  Close up the monitor and we're done.







Although this mod does not leave room for the touch screen, I can say that I am significantly happier with the way this turned out. This mod leaves me with an external blu-ray player and plug and play monitor. It is clean and simple without any visible wires or shelves on the back of the monitor.  I know this does not show every single step, so if you have any questions feel free to ask.