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Performa 5xxx Monitor as Monitor


Well-known member
... Is there any way to use a Performa 5400/120 (with TV kit - not specifically relevant) just as a monitor.  For instance, could I put a desktop beige G3 under the Performa and for space reasons use the Performa just in a a monitor state [it sounds dumber each time I try to rephrase it in my head...]  I'm guessing this would require major (ugly) hacking?



Well-known member
Major ugly hacking job - you could get the monitor pinouts on the edge connector/harness to do it.  Perhaps look out for an older 15" LCD which matches the beige G3 for less space



The cleanest way to do it would be to, as Byrd suggests, find out the relevant pins on the edge connector, make up a small card to go in the slot, and break that out to a VGA port on the back panel.  A DIL header might be handy for patching sense lines connections and diodes.  You could probably bodge something up on stripboard pretty easily.  Then you just have to make sure your card goes in the right position in the slot and stays there.

Come to think of it, that last problem would be fixed by using a dead 5xxx motherboard, cutting off the whole edge connector section, and soldering leads to the edge connector traces or nearby pads.

Then you just need a way of tricking the analog board into powering up.

This would be reversible, as you could pull your board out and replace it with a 5xxx series motherboard any time.

If anyone out on the web someplace has done a 5xxx ATX/Mini-ITX mod, they probably have all the necessary clues.

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Or if you don't mind fiddling with small wires, hack it on the ribbon cable.  An optional multi-pole switch could let you choose between motherboard video (and power) and external video.



Daring Pioneer of the Future
Staff member
You could also give using a/v a go -- if your beige G3 has a Wings card, set the desktop output to the video port, plug that into the TV tuner on the 5400 and launch the tv/video app, switch to composite or s-video in, and enjoy low-res desktop usage. I used my 840av with a TV for a while, it's possible, but not pleasant. I don't know if it would be any better on a Mac's display with video input.



Well-known member
Ive done that very same thing before with my old 5200/75, Using it as a monitor hacking in a motherboard. 

But as everyone suggests, you have to hack the harness going back to the analog board, and tie in a VGA cable to it. Not fun, but it can be done!

Using the Q630+ edge connector pinouts on the web, its really easy to do as it follows the same standard as the LC580+ or takky/mystic CC. 

Being able to switch back and forth, you would have to hard-wire a VGA A/B switch between the original mobo, and your external device. Be careful with grounds though, because it can cause image "ghosting" 

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