20" cinema display goes black when I plug either usb or firewire cable from display into G5. What's wrong?

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Level 2

178 points

20" cinema display goes black when I plug either usb or firewire cable from display into G5. What's wrong?

I did find one internet posting that described this same problem, but only one. Just got a used 20" cinema display with usb and firewire cables bundled with the DVI connector. If i simply cable the DVI connector to the computer the monitor works fine. But If I plug in either the usb or firewire connector anywhere on the G5 the screen goes black. Unplud the cable and the screen comes back. I'vbe looked for driver or firmware updates but found nothing for the 20" display.

G5 (PPC) dual 2.3 GHz, OS 10.4.11

Anyone have any ideas why this is happening?

G5, dual 2.3 GHz, 4 GB RAM, Mac OS X (10.4.3)

Posted on Feb 12, 2014 8:36 PM

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Answer 1

BDAqua

Level 10

250,259 points

Feb 13, 2014 12:05 PM in response to Jeff Dooley

Hi Jeff,

My guess is a power supply problem, or The USB/FW Bus is messed up, that is what it was on my 17" ADC Cinema.

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Answer 2

Jeff Dooley Author

Level 2

178 points

Feb 13, 2014 1:12 PM in response to BDAqua

I'm leaning toward suspecting the 65w power brick of delivering insufficient power to the monitor to drive the USB/Firewire load. Gonna try a different power brick and see if that makes any difference.

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