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philgxxd

macrumors 6502
Original poster
Feb 11, 2017
424
342
Malaga, Spain
@eyoungren or others

Since I got that rare FORMAC branded ADC to DVI adapter I always wanted it to use for my dual acrylic Cinema Display setup on my G4 MDD.
My idea is to connect both monitors through 2x Apple DVI to ADC adapters I have so that the power supply from the G4 doesn't have to deliver the power and doesn't get so stressed and hopefully prolong it's lifespan.
But I can't get to output any image through that FORMAC adapter.
I only got once an image when I hotplugged the monitor while the system was running but got some nasty distortions on the screen and after replugging it in it didn't come back and I wasn't too keen to keep trying hotplugging.
The adapter itself seems to work as I can get an output when I connect a HDMI monitor to the FORMAC one with just another DVI to HDMI adapter.
 
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I am confused.

Your title seems to indicate you want to pass ADC from one display to DVI and then back to ADC?

I am guessing you are trying to hook this Formac converter up to your G4 (which has an ADC card?) and then pass DVI from the converter to two A1006 bricks?

Do I have this right? Or totally wrong?
 
Untitled Diagram.jpg
 
I think the ADC-out>Adapter>Adapter>ADC-Monitor (right version) will be more distressing for your PowerMac, than the direct monitor-ADC-connection, which was meant as the primary way to connect the Acrylic Cinema Display...
 
OK. I think I got it.

What you want isn't going to happen (ADC with the DVI back to ADC). Perhaps someone else could explain because I don't have the words for it. It's got something to do with how the signal is routed though.

You'll need to get a video card with dual DVI or just hook the display up directly. The power draw from the display isn't going to affect things.
 
The power for the display come from its own 24V "section" of the PSU. It's sized to power the 17" CRT...none of the acrylic LCDs draw anywhere near the amount of power the CRT needs.
 
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Well thank you all for the replies.
I was maybe overthinking the issue so i will stick to how it is connected now and working properly minus the USB ports on the 22" Display which
seems to finally stopped working.
Do you have experience with that USB ports on the acrylic monitors ?
Is there something i can try to revive them ?
When i connect a mouse to them it's getting power but that's all, no moving cursor.
 
Check for bent or damaged pins perhaps? Wiki states pin 21-23 are for usb.

I will look for it. Thanks.

Did you swap monitors at the ADC-out of your PM to check, if the problem is related to the monitor or the PM?

It's the monitor as the other one have the USB working fine when I connect it to the ADC port directly. I have there two dongles installed and never got problems to be recognized.
 
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