Here's the situation:

I have a bondi blue imc g3. no issues with it other than it's old n slow.

i also have an ibook g4 1.2 ghz logic board from a repair i did a while ago.  the board works absolutely fine other than the internal video issue.  see external video works just fine, but the internal to the lcd only shows grey screen. have tested it with different lcd's, inverters and wires. internal video is just dead.

My idea is to put the logic board in the bondi imac. i have been thinging about this for a while and am only stumped on the following 2 things.

1. who can i use an external vga adapter and hook it up the the imac's crt

2. how can i use the imac's powersupply to power my board?

i have tons of extra ibook parts from lots of repairs i have done, but just thought i would spruce up the old imac. If anyone knows of a tutorial of this being done before or has any information on the rewiring that will have to be done, please let me know.

thnx for the advice.

but i would like to do the job as best as possible. what i was hoping to do is feed the ibook board off the same power connections that would go to the imac board (some adjustments would need to be made).  was also looking to hardwire the video wires that would connect to the video port (coming from crt) on the imac board to the external video port on the ibook board.

the powerbutton would just need to be connected to the on/off jumper of the ibook board.

my main concern is finding a guide the tells of the wires for video for both the imac and the external video port on the ibook and also of the power issue. not sure of the amps supplied to the imac board. so may need an additional psu to go between the imac power supply and then to the ibook.

The iMac board almost certainly uses less juice than the iBook. Your best bet is to get a multimeter and check the various voltages at the power connector on the iMac logic board. Then check the voltages you are getting at the DC in board on the iBook. If you are lucky, the iMac will already have the right voltages for you to wire to the DC in board (You could even skip the DC board by measuring the voltages where it connects to the logic board). If you can do that, then you can very simply sever the iBooks power switch and splice it into the iMacs, leaving all the original iMac power switch wiring in place. Then both the iBook board, and the CRT will power on at the same time.
If your iMac is one of the original tray loaders, then it actually has a standard VGA (or maybe DB-15) connector inside. So hooking up the video will be easy.
If its a slot-loader, you may find it more difficult.

Got that first line the wrong way around. The iBook board will use less juice. Stupid overuse of the letter i.........

The iBook Power Plug Puts Out 24v. the imac puts out, well, take a look for your self.
http://members.fortunecity.com/tinux1/sites/imac-atx.html

If you stick in an LCD like http://www.macmod.com/content/view/414/193/, it would most definately fit. Just go to an ex government auction and they'll have plenty of 15" LCD screens. That's where I got mine. Though it's not in my iMac. It's connected to a ThinkPad running XP and AverTV.

Looks like you might need to do some serious PSU hacking. If you have room, a late PowerMac G4 supply might be a good bet. The 28V they put put for ADC displays is often closer to 24V in reality.