Thursday, September 29, 2011

The 17" Mod Success Stories, Mistakes, and All-In-Ones

As I just wrote on my 17" iMac G4 guide, I have been exploring simpler ways of converting the iMacs LCD to a plug and play DVI/HDMI compatible monitor.  Do to an upcoming test I have to put this project largely on hold for the next few weeks.  Regardless, people have been doing great and over the past few months I have gotten emails of no fewer than 10 successes.  Many from people with limited electronics experience.  Thank you to everyone who has shared this me, its extremely rewarding to see that my projects have helped others doing the same.  I hope to see plenty of broken iMac G4's returned to their proper place on the desktop for years to come.
Courtesy of

I have unfortunately wasted time going down a dead end route.  After much searching I was finally able to locate the motherboard receptacle for the iMac G4's video cable.  For those interested it is the 21pin - C seen in the diagram to the right.  Specifically its the: 656-FI-WE21P-HFE JAE FFC / FPC Connector.

My hope was to create an adapter wire that you could simply plug into the iMac's video cable.  It would have a DVI/HDMI out and cables that could hook to a power supply.  Add the inverter and presto, instant iMac conversion.  Unfortunately the ones that are soldered on boards need to be ordered in the thousands.  The actual connectors themselves are too difficult to work with unless pre soldered to a board.  I've tried but the pins coming off very small and the crimping tool that you can buy is around a thousand dollars.  The current method that I'm trying the use seems much simpler (and cheaper).  I will detail it in the guide as soon as I complete it.

Top = MALE
Bottom = FEMALE
The biggest "correctable" error that people seem to be making involves using the DVI pinout as is with a male cable.  I talk about this in the post, but I think people are looking only at the pinout.  So I'm going to make it clearer and post a male pinout.  The DVI pin numbers are based on a standard numbering system which is numbered left to right based on the female DVI connector.  The female connector is what you plug a standard cable into, found n the back of a computer or graphics card.  The standard DVI cable has 2 male connectors at its ends.  So please keep this in mind when you do this mod.  You can certainly use a male interface, but you have to realize which pin is which number.  You can simply view it from the back to see how it relates to the female plug.

In regard to all-in-ones, they are certainly possible.  But just keep expectations in check.  You really can not fit much it the base.  And remember you have to power it.  Pico power supplies really are limited to about 150 watts so if you want and you can not fit an tax power supply in the base.  But, remember this is a 17" screen - you don't really need a powerful video card.  That said, I still firmly believe that a mini itx is too high a risk for overheating at the bottom of the dome and should not be used.  I recommend using a pico, nano, or embedded motherboard.  I'll be reviewing some of these choices in my next post.