Monday, May 13, 2013


Sorry about the delay but...

After completing my latest mod, I promised a guide.  Due to personal reasons, I have not had a chance to work on this.  As time goes by and it is less fresh in my mind, it becomes somewhat more difficult to compile.  While all the information to do this mod is within this blog, it is not very well organized.  The Monitor to DVI instructions are contained within the 20" Sandy Bridge Guide.  While I talk about the native power source in this tutorial, I use a PICO power supply in this actual mod.  The native PSU is really discussed in a different post.  Likewise, wiring up the new NUC board is in a different post altogether.

I had initially constructed this site to be a "Tech Journal/Diary" where the most recent updates would be chronologically first and older entries could contain outdated or incorrect information.  As I became more involved in the iMac G4 project, this site became more of a guide/tutorial site.  While this isn't a bad thing, its just not exactly how it was designed to be.

As I've been putting together the tutorial for the 20" Ivy Bridge NUC Mod (in the form of audio over pictures), I've realized that this may be the opportunity for a "redesign".  I would like to keep this site as my tech journal site.  Even the failed mods and the process behind them is something I would like to "preserve".  I have secured "" and I am hoping to eventually link between these two sites for a more cohesive and straight forward experience.  Someone wanting to know how to connect the native PSU can click on it and either go to a written tutorial, video guide, or original dremel junkie post.

It is certainly not lost on me how confusing it is to google "iMac G4 Update" and think you've found the answer only to find several posts detailing somewhat related (but not the same mod).  Also, from my end, I have step by step photographed, documented, and wired up two different 17" necks (one on video) and a 20", and am now going to repeat it again for the 20".  This will allow me to have a "modular" approach where 'for instance' STEP B: Conversion to DVI remains the same regardless of which computer you use in the base.

I would greatly appreciate any advice from those more skilled than me at web site creation.  I would like it to be simple and easy to follow, but am a novice at this.  Please let me know if you have any suggestions.

The 20" NUC Tutorial

I want to assure you that this will not interfere with the 20" NUC tutorial.  The biggest hold up has been the fact that I am not 100% happy with the amount of pictures and detail that I captured.  My goal was to complete the mod and I was not as thorough with photographing and documenting the steps along the way.  Although I do not have a problem opening up my mod.  There is no doubt that I will have to do a decent amount of disassembly to get the pictures I would like.  If I am going to disassemble my mod, I would love to upgrade it in the process if possible.  Luckily, it does appear upgrades are not far off courtesy of Intel and Gigabyte:

From Gigabyte - The Brix:

Courtesy of
Courtesy of
This NUC based system is smaller, lighter, has more I/O options and will have i5 and i7 options.  While initially Ivy Bridge based, Haswell is likely not far behind.

And Intel:

Rend Lake will be i5 and USB 3.0 capable based of Ivy Bridge Architecture.

In retrospect the use of Thunderbolt was a waste on the initial NUC.  Initially I thought it would be "future proofing", but its been months later and the only intriguing peripheral is Belkin's (finally being released) $300 Thunderbolt dock.  Of course, its the USB 3.0 that makes this dock interesting.

Thus, this NUC should be far more versatile (at least I hope).

I am unsure of the variation in the "Horse Canyon" Core i5, it doesn't appear to use a Haswell Chip, though I can not be sure.

"Skull Canyon" is the Core i7 Variant, and the one for which I am most excited.

Of course, updates are always going to happen, and while these are only incremental upgrades, I have been looking for an opportunity to add USB 3.0 in particular (and get rid of the thunderbolt).  As these seem like they are "around the corner", I am asking for patience in terms of the guide.  Replacing the board is not difficult, but it would make more sense to only disassemble and reassemble this mod once.

So please stay tuned and hopefully the tutorial will be done shortly, with an even more powerful NUC serving as the computer.


Some of you may have noticed an"incompatibility" with certain sources.  Sometimes this is due to playing digital protected content "HDCP" or even using certain motherboards.  For myself, the EPI-QS77 and I am told the Raspberry Pi as well, seem to cause incompatibility issues.  In some cases, changing from DVI to HDMI and back can remedy the problem, other times, artifacts persist in the monitor.  My guess is that some boards may have an incompatibility with the "EDID", the identifier of this LCD.  While there is no direct way around this, there is an "indirect way".

The White Polycarbonite Family
As I have mentioned before, prior to figuring out direct wiring of the existing LCD, I had found a work around.  This "work around" is used in the iMac G4 (pictured above) and although its just serving as a monitor (with a modded iMac G5), I have now been using it daily for over 2 years without any problems whatsoever.  This work around keeps the native inverter and can keep the LCD or use an LCD from an aluminum Apple Cinema Display or iMac G5.  The most important thing is that this uses the controller board from an apple cinema display.  While this does involve opening and rewiring the neck, it does give the LCD a true EDID and HDCP compatibility.  There are certain other advantages as well, but it is more technically challenging and will require some parts from a cinema display.

I mention this only to gauge interest.  Are there people who have experienced this problem? Are people interested in this particular method?

Thank you all again for your patience and thank you for taking the time to read this.


  1. Hello Mr Junkie

    I've just bought a 1ghz 17" G4 to mod for use with my raspberry pi (i intend to use it as a XBMC HDCP). I know that at least one person has tried this and had HDMI issues, as you allude to in your post.

    I had intended to do the straight TMDS to DVI conversion (Mod 4), but do your comments mean that i need to apply the Cinema Display Controller mod (Mod 6A)? If so, does your guide also apply to the 17"?

    I realise you may not be familiar with the RPi, but is this an issue which could be resolved by forcing the correct HDMI mode etc (technically, i'm a moron).

    Keep up the good work!



    1. If anyone is interested, i have successfully enabled the RPI for the G4 display (i.e. can see text and images), but still working on settings for resolution (the screen is tiled).

      Email me for info -

  2. I have worked out the solution for the Raspberry Pi. The issue is that the G4 EDID is not recognised by the Pi, and the preferred resolution is not within the standard RPi presets (even though it appears to be). Thankfully, the RPi people have allowed editing of the config.txt for custom resolutions (see

    I have got it to work perfectly on my 17" G4 using the following entries in the config.txt:

    hdmi_cvt 1440 900 60 5 0 0 0
    config_hdmi_boost=7 (I think this value was necessary for my longish DVI-HDMI cable. Adjust as necessary to remove artifacts.)

    Make sure there are no other display entries (although you may need to fiddle with overscan once you've got it working).


    1. ps if you have a 20", just use the default resolution (i think its 1680x1050, so the first entry above would be "hdmi_cvt 1680 1050 60 5 0 0 0"). Can anyone confirm that this works?

  3. I love you Crusty. That is all.

  4. Because of personal reasons, you have not had a chance to do this. And now everything can be done, you have shared this with us. friv 4