Pages

Thursday, July 28, 2011

Optical Drives, Mac Minis, and Thunderbolt

Courtesy of apple.com
So the final part of my setup is "the actual computer".  I decided to go with the higher end non-server model.  I would have gone with the server for its quad core i7, but discrete graphics is quite important to me.  I have had some so-so experiences with onboard intel graphics in the past.  In terms of upgrades - I very much wanted a SSD, but for $600, it was not going to happen.  I have spoken to people who have changed or added drives to last years mini (same design) and while not simple it is doable.  So I went with the base 5400rpm 500GB drive knowing that eventually I'll likely add another drive or swap this out entirely.  I did decide to invest in the 2.7Ghz dual core i7 processor as this is something I won't be able to replace later and at $100 the cost wasn't ridiculous.

There was one "surprise" for me, I was not expecting the demise of the optical drive.  While this does cause me to alter my design, it really is not a big deal for me.  That said, I am somewhat disappointed in the decision.  The reason I say that is because it decreases the versatility of the machine.  Plenty of people viewed this as an ideal and elegant HTPC, many of those people have DVD collections, instead of an iTunes movie library.  For the Macbook Air - the initial decision to loose the optical drive allowed the chassis to become even thinner.  In the case of the mac mini there is an empty bay.  The design hasn't gotten smaller and unless you have two storage drives there is simply empty space.  Even if a drive wasn't included in the base model, an option for a Build to Order one would have been nice.  Optical media may not be the future but for many people it is the present and as small as it is, the mini is still a desktop computer.  Obviously, Apple can do what they want and as a huge media digital distributor they have a vested interest in seeing optical media disappear as soon as possible.  But, I thought they could have waited another generation as the people I know who waited for this machine as a living room computer have not decided to go digital, but have instead gone in a different direction.

This does open up some design potential for my setup which uses a converted iMac G4 and iMac G5:

While my initial design included a bluray drive in the base, I took it out as I thought it was redundant with the mini on the desk.  An internal drive was less complicated when there was a computer in base.  As this attached simply through an SATA + PWR connector to the motherboard.  While SATA to USB + Power brick adapters are available, I would like to keep the design as simple as possible.  Meaning I would prefer only one AC plug, no external power bricks and as few cables going between the mini and and the iMac G4 chassis as possible.

For there to be only "1 plug" I obviously have to split power off somewhere.  I can do this on the "AC side" before the power brick or on the "DC side" after the power brick.  I have an old 5.25" external drive enclosure that I have no further use for.  This includes a small power supply and onboard SATA to USB.

With some internal rearrangement I should be able to fit both the power supply as well as the drive.  Currently all that is in the base is the Cinema Displays LCD controller and Power Brick.  I am hoping to keep the power supplies at the top of the dome.  The drive in the middle and the controller on the underside of the drive.  Leaving the very bottom for some wire management.

Using the Cinema Display's on-board USB ports will allow me to connect the drive and replace the "used" USB port with one that will be on the back of the iMac G4s base.  In addition I will add either the rocker switch or a push button on/off to the back of the iMac G4 for the drive.  I do have the option of Firewire 400 ports but will probably not hook these up.  Although there is not currently any reliable support for it, I do have a full side 5.25" tray loading bluray drive which has already been modified to fit in the iMac, so I will probably be using this.

Courtesy of CNET
Another option is to use the iMac G5 or both.

PicoPSU by Mini-box.com
Of course, as I have previously noted, I have plenty of room in the iMac G5's chassis.  The way I felt this looked the best was to mimic the original look, whereby one cable comes out the back.  So the Cinema Display's Cable comes out the hole n the back, which I will eventually surround with white rubber to make it look as clean as possible.  As a result, the power brick is external.  To use an internal slim slot loading I need an SATA power source (12V), but the power coming in via the Cinema Display is DC at 24V.  In order to siphon off power I need a DC to DC voltage regulator or power supply.  I chose a picoPSU which can use 24V input.  I chose this because it was cheap, small, gives me lots of options, and I am familiar with it.

Using this and a SATA to USB I can again use the onboard USB slots of the cinema display.  And as I am already connecting the Cinema Displays cable to the computer, I may hook up the firewire 400 ports and connect them to the back of the monitor where they were designed to hook up to the iMac G5.

Back Panel Thunderbolt - Courtesy Apple.com
In my opinion one of the most interesting products Apple just launched was its new Thunderbolt display.  The idea that one cable (externally no different than the display cable) can turn the monitor into a "dock" is brilliant.  What would be ideal for my setup would be if they ever sold a separate "Thunderbolt dock".  A Thunderbolt cabe at one end with a mini display port, USB, firewire, ethernet, thunderbolt out (for daisy chaining) etc at the other end.  This would allow all sorts of devices/accessories to be stored in the iMac G4/G5 housing.  An example may be using Macbook Air with onboard Intel HD3000 graphics hooked up to a modified iMac G4 or G5.  But inside of the iMac enclosure is not just an LCD but a powerful PCI-Express graphics card hooked up via thunderbolt (I know it wouldn't be fully x16 - but it would still be very capable) as well as a 3TB HD array and Bluray drive that all becomes accessible as you hook one cable up to your laptop.  It really may make these mods more than just monitors.

Sunday, July 24, 2011

20" iMac G4 Inverter Pinout (Not tested)

Based on the voltages from my current setup with the Apple Cinema Display as the power source.  You should be able to hook this up to a native working iMac G4 20" power source, but as I do not have a working one I can not confirm this.

iMac G4 20" Inverter Pinout
To be honest I am not sure exactly what the yellow wire does and I can not guarantee that there is not something else missing.  I believe its also involved in on/off control.  I am not sure about what resistor as I do not know the current, but it would be high - at least 1Kohm.

The TMDS to DVI for the ID Tech panel can be found here.  Again this is based on ID Techs own specifications, so I am very confident about in this pinout, but have not tested it myself.

If anyone does have a power source and gives this a shot please let me know the results.  Good luck.

20" LCDs, Signaling, Inverters, and Pinouts

After getting some questions, I realized that it isn't very clear on my blog what makes the 20" iMac G4 different from the 15 and 17" models.  Simply put the difference is the inverter and powering the backlights on a 20"LCD.
Monitor Components

I) Intro - LCDs
To explain just some basics about LCDs: (I am no expert so please forgive me if things are slightly wrong or grossly oversimplified).
Most monitors (that connect to an AC power source) contain the LCD itself and then two boards. (See image on the right)
1) Top of the image is the LCD controller board.  This is where DVI/VGA plugs in and gets converted to a signal type, usually LVDS.  The controller also connects to a power button and some other control buttons.  Thus, the board can adjust aspects of the image such as brightness, contrast, position etc.
2) Bottom of the image is the Power Source/Inverter.  AC Plugs in here and powers the backlights (connectors at the bottom).  The backlights traditionally CCFL lights (now more LED) allow you to see the displayed image.  The AC is also converted to DC and supplies power to the LCD controller and via the LCD controller the LCD panel itself.

JAE connectors
II) Signaling Types
LVDS (Low Voltage Differential Signaling) along with power (usually 5 - 12V) and ground wires go from the controller to the LCD via a multi cable connector - usually a JAE connector.

Every Apple Product involving an LCD that I have worked on so far works somewhat differently.  This includes all the iMac G4's, the 20" iMac G5, and the 20" aluminum Apple Cinema Display.

The major difference is that the Type of signaling used is TMDS (Transition Minimized Differential Signaling).  While I do use the term "TMDS to DVI conversion" in my blog, this is actually a misnomer as there is no real conversion.  TMDS is the type of signal that DVI and HDMI cables use.  Nothing gets converted, its just that the wires get arranged in the right sequence and POWER is added.  Inside the LCD casing itself there is a Texas Instruments chip that allows the monitor to utilize the TMDS signal.  Therefore, ALL of the LCDs in the above computers can be connected directly to any TMDS signal - meaning any source that sends a signal over a DVI or HDMI cable.

Panel Names: (May not be complete) - All TMDS compliant
iMac G4 17" - LG LM171W02(A4)
iMac G4 20" - IDTech M201Z2-M01
iMac G5 20" - LG LM201W01(A5)(K1, K2, or K3)
Aluminum Apple Cinema Display 20" - LG LM201W01(A6)(K1)

III) LCD Controllers
Inside the Cinema Display
DVI going directly to LCD
Even though all the data goes directly to the panel, there are still LCD controllers.  In the case of the iMac G4 and G5, the controller is in the motherboard.  There is no conversion of signal, but power to the panel and brightness is controllable.  There is an LCD controller in the cinema display.  The actual TMDS data cables go directly to the LCD from the DVI cable.  The ACD's LCD controller does add the power to the display and changes brightness, connects to a power button, and is also a USB/Firewire hub.

Again, for all these panels, you can connect DVI or HDMI wires directly to the LCD's JAE wires.  As long as you also supply power for the panel (12V for the 20" panels and Grounds) as well as forgo hardware control of brightness - you will produce an image.  But, you will not be able to see the image without backlights.

IV) Inverters
Like any monitor with CCFL backlights you need to AC power.  The iMacs do not need a power source because the computer itself already has one.  DC voltage goes to an inverter that turns the DC voltage into high AC voltage (>1.5 Kilovolts) allowing the bulbs to turn on.  The Cinema Display actually works the same way.   The external powerbrick is the power source, taking AC and putting out 24V DC.  So even with a working image you need an inverter to turn on the backlights to see it.

For the 15" iMac G4 other modders were able to figure out what to feed the inverter to get it to turn on.  They used an ATX power source.  I determined the 17" iMac inverter pinouts because I had a working inverter, power source, and although it froze with booting - motherboard.  So because there was an image I was able to determine what voltages went to what inverter cables to turn the backlights on.  I then used an AC to molex adapter (Gives 12V, 5V, and Ground), approximated the voltages (I didn't have a 3.3V line), and turned on the backlights.

So here is the problem with the iMac G4 20".  First, no other inverter which can power the backlights that I have found is thin enough to fit in the case.  Trust me I've tried a lot - See this post for details.  So while there was only 12V, 5V (3.3V recommended but not needed) for the 15" and 17", the 20" was not so simple.  Remember all these voltages are easily available from any ATX power supply.  The 20" inverter needs a 24V power line.  In addition, while I can identify the power lines, grounds, on/off, and dimmer of the other inverters, there was an extra wire with the 20" that I'm not really sure what it does.  So, you need a power source capable of 24V, 12V (to power the LCD panel), and 3.3V - any old ATX power supply will not do.  The native iMac G4 20", G5 20" or 20" ACD all have power supplies that do have a 24V output.  That was original reason i was using the Apple Cinema Display in the first place - I did not have a working iMac G4 20" power supply.  What complicated things further was although I had a general idea, I could not determine voltages from a multimeter, thus it was guess and check.  Unfortunately, when I burned out an inverter I realized that this method wasn't going to work.

V) Solutions
Using the controller of the Apple Cinema Display solves the problem.  The controller is really a series of resistors that takes the 24V DC and splits it up into the voltages needed to power the panel and the inverter.  Plus it adds on/off, brightness control, and a USB/Firewire hub.  But, this is essentially the same as the "TMDS to DVI conversion for the 20" that I posted here, as far as the TMDS data is concerned.  Using this controller simplifies and stabilizes the system very well.  This is obviously not the most cost efficient method.  However, buying a working 24V power source can be expensive as well, so if you need to buy one anyway, I would recommend going for a cinema display with a broken screen.

But for those of you that either have a working iMac G4 20" power supply or some other 24V source there is obviously a way to get it working.  Now that I actually have a set up that works, some may wonder if I can now determine what DC voltages are needed to "activate" the native inverter.  The answer is yes and I have already done so - I will post the inverter voltages in my next post.  Two things about this are unusual. For one, there is a yellow wire with an extremely low voltage, I believe its part of the on/off mechanism or backlight control.  I am not sure if there is something else that I am missing with this wire.  Second, I have given just the voltages, you will need a fairly high resistor for the yellow wire even if you connect it to the 3.3V, but I don't know the current of the power supply to calculate it.




Sunday, July 17, 2011

End of a Generation?

An Homage to the "White Plastic" Generation
In the past few weeks there has been conflicting information about the future of the white macbook.  Initially a new part number was thought to belong to an upcoming refreshed macbook as 9to5mac reported here.  I was somewhat surprised by this as I expected the refreshed MacBook Airs to spell the end for the white macbook.  Now with a leak on apple's own site, it would appear that the part number did not refer to a refreshed white macbook, but rather to a new Thunderbolt equipped cinema display (Reported on TUAW here).  The reason I'm mentioning this is because this site has been dedicated to modifying the iMac G4 so that it can be used with modern hardware.  The iMac G4 represents the beginning of the "white plastic" era for Apple's consumer line.  It continued in the desktops consumer as the iMac G4 transitioned to the iMac G5 and even through the transition from PowerPC to Intel processors.  Similarly it started with second generation iBook before the consumer notebook line converted to Intel.  But, even as iBooks became Macbooks, they retained their white polycarbonite design.  Before this Apple products were quite different.


iMac G3


Clamshell iBook

In the early 90s, Apple computers, for the most part, looked just like the "beige boxes" of their competitors. Following Steve Jobs return to Apple the design aesthetic became very colorful, almost whimsical.





Designs included bright pastel colors and translucent plastic.  Multiple colors were available.  Although more interesting than other computers at the time, I was never a huge fan of this design. Though interesting, it wasn't as elegant as Apple's later designs.




The iMac G4 ushered in the new polycarbonite white design for computers (likely taking cues from the newly released iPod).  Although I love the design of the iMac G4, I also loved the G5.  That's why I am using that design as my second display.  They were simple and clean.  Their industrial design still looks "futuristic" despite the fact that they are several years old.  They were both radical designs for computers back in the day.  LCD all-in-ones really didn't exist.  The iBook to Macbook followed this design aesthetic despite the addition of unibody construction and the glass trackpad.

As the line between consumer and professional products becomes more and more blurry - traditionally "higher end" materials such as aluminum and glass have now become standard across Apple's entire product line - even the "low end" mac mini is aluminum.  I love the newer designs and think the Macbook Air in particular is extraordinary.  However, if this is the end of the white macbook it is a little bittersweet for me as it marks the end of an era.

Courtesy of iTechSoup

Wednesday, July 13, 2011

Video of 20" iMac G4 All-In-One ECX Mod


Before I removed the contents of the base to convert this mod to an external monitor for the mac mini I shot a quick (and shaky - sorry) video demonstrating its use.  I have stored all the contents including the bluray drive and ports.  The new Quanmax ECX board is due out at the end of the month and if it is not cost prohibitive - it could quickly be reassembled.  I'm hoping that, for one - there are new mac minis and secondly that they do not disappoint.

 For those of you interested in doing this mod, but wanting an all-in-one - use an ECX board - trust me.  I spent hours trying to shoehorn a mini itx into this thing and have spoken to plenty of modders who have done the same.  I bought all right angle port connectors - tried all angles.  Eventually I'd get it to close, but then within a couple hours I had to reopen it for something. (Short out, wire hitting the fan etc.). The one person I know able to get it closed and working has to power down periodically as a result of heat issues.  The base is a very poorly vented thick metal cage.  There are a few slits at the bottom and holes at the top.  Apple designed this to be convection cooled.  When I had updated the inside RAM in an original iMac G4 I forgot to put thermal paste on the two heatpipes when I closed it back up and the iMac would not stay on for more than 2 minutes - that's how delicate the convection cooling system was.

Mini itx in bottom of dome
The unavoidable flaw with a mini itx board in this setup is that it has to sit at the bottom of the dome (its the only place it fits).  So everything is above it.  There is no way to fit a DVD/Bluray with a mini-itx as the RAM and heatsink come up way to high.  Despite removing this, at minimum you will have the hard drive (even a small one), a power supply (The ECX board connects from a 4pin to external power bricks), and lots of wires that will all occupy the area above mobo - obstructing what little airflow there is.  And its a long way up to those small ventilation holes at the top of the dome.


Native HDD and DVD vs. BLURAY and ECX Mobo
The ECX is 3.5" (the exact same size as the native hard drive).  You can easily put a SSD below it or at the bottom of the dome (mine has a CF slot), and it does not require a separate power supply.  Most importantly the ECX by virtue of its size can sit at the top of the dome with its fan right under the ventilation holes.  And to be honest it was still pretty hot!! But at least not dangerously so.  For those interested ECX boards come in many varieties.  Quanmax and Portwell are two of the bigger manufacturers.  I am waiting for the new Sandy Bridge line, but there is nothing wrong with some of the newer Atom boards. Lets face it - if you are doing a 15 or 17" mod its probably not going to be a gaming computer.  As a secondary computer, it would probably be more than adequate.


Photo courtesy of Electronista
In terms of opening a mac mini - I'm not sure - while its designed to be very low voltage it would have to sit at the bottom and therefore heat is likely to be an issue.  To be honest, I kind of consider this now a moot point.  The newer mini design is likely here for the foreseeable future and although thinner, its mainboard is now likely too big to fit into the dome.  The previous generation core 2 duo will fit, but without a clear upgrade route I wouldn't risk taking it apart.

Question, Comments, and Advise always appreciated!

Wednesday, July 6, 2011

My Dream Setup - iMac G4 and G5 - Dual Monitors

The iMac G4 "mac mini monitor"
Although this has been a great hobby for me, my goal has always been to produce a computer and setup which allows me to use the form factor of the iMac G4 with modern hardware and the Mac OS.  As you can see from my summary, most of my mods - besides the black iMac/VESA - have been disassembled for parts as I feel that the mods have gotten better and I simply don't have use for that many iMac G4 hacks.  The fact that I have completed a 20" all-in-one iMac G4 complete with ports and a blu-ray drive using the ECX core 2 duo board shows me that this mod is doable. The only negative is problems with snow leopard (and presumably Lion) with this board.  However, there should be no compatibility problems with the new Sandy Bridge KEEX-6100. Still, I have expressed my reservations with hackintoshes in the past and I would prefer a true mac.  So while I have been using my touchscreen iMac/Cinema Display mod with my old mac mini, I have really come to prefer the appearance of my newer mod, the native iMac G4 all-in-one mod.  So after filming a video of the all-in-one mod and much deliberation, I decided to disassemble this mod and "switch" this mod with the apple cinema display one.  Thus, I will get the benefit of a brand new/white exterior and the native housing which makes this completely indistinguishable from the original iMac G4.  I will however loose the touchscreen.  I simply felt that this came closer to what I originally set out to do.  For myself I do not mind the small footprint of the mac mini being on the desk as well.  Plus, this leaves open other possibilities such as using it as a desktop monitor for my Macbook.

Two Ports: DVI and Power
I did decide to make one additional switch.  Although the mod works fine with the original iMac G4's LCD - the apple cinema display's LCD has a better contrast ratio, viewing angle, brightness, and response time.  I had an extra apple cinema  LCD (which was intended for the mod detailed later in this post that I ended up not needing).  So I replaced the iMac G4's LCD with the Cinema Display's.  Here you can see photos of the new iMac G4 hooked up to the mac mini and apple pro speakers via the iFire adapter.


From the back
 I left out the bluray drive (as Mac does not yet support it), but now have plenty of room for the power brick which is now included internally.  So only a DVI out and C14 Plug is required on the back.

iMac G5 with Cinema Display Cable
My ideal setup has multiple monitors.  Unless I have a 27" screen - I find having the extra screen real estate important for multitasking.  At first I considered two iMac G4s but thought that may look odd.  So I decided to add my second favorite iMac design of all time - the iMac G5.  I obtained a broken 20" iMac G5 in good cosmetic condition and removed all but the lcd itself.  I had an extra apple cinema display with a broken screen - I put the cinema displays components around the native iMac G5's lcd (which luckily still worked) and I now have an external monitor in a G5 shell.  For now I just wired the cinema displays cable out the back where the C14 plug used to be.  There are still some issues to work out such as the monitor now being very light.  Also, the screws in the bottom no longer fasten into anything.  And, I do plan on wiring the 2 USB and Firewire 400 inputs of the Apple Cinema Display to make them accessable on the rear panel of the G5.  I know I did not go into detail on this mod - as there really isn't much to it.  Just know that the native iMac G5 panel works with a cinema displays controller board.  If anyone is interested in this, please let me know and I will add a step by step and parts list.  And if you are wondering why I didn't use the TMDS to DVI hack, its because I would still have to power the iMac G5's inverter which also requires a 24V line.  Sure, the iMac G5's power supply could be altered, however, the power supply on this was broken and I had the cinema display components.

On the 20" iMac G4
Unfortunately, my mac mini does not support dual monitors (the current one does).  I am hopeful of a new Sandy Bridge mac mini which will be the centerpiece of this setup.
So first the iMac G4 connected to the mini.

On the 20" iMac G5
Then the iMac G5 connected.  And hopefully in July...Both!










As always comments, questions, and suggestions are appreciated.  Thanks for reading!