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sammyman

macrumors 6502a
Original poster
Mar 21, 2005
998
65
I have a 1,1 Mac Pro with a GT120 512MB video card. For some reason, the DVI doesn't work. The Minidisplay port works fine. Just no DVI right now. I've never had an issue like this, and don't know where to start diagnosing it. Any suggestions?
 
I have a 1,1 Mac Pro with a GT120 512MB video card. For some reason, the DVI doesn't work. The Minidisplay port works fine. Just no DVI right now. I've never had an issue like this, and don't know where to start diagnosing it. Any suggestions?

You could start with what display(s) you are using, how you are connecting, what OS, what drivers.

Basically, details.
 
You could start with what display(s) you are using, how you are connecting, what OS, what drivers.

Basically, details.

Thanks. I have a 23" Apple Cinema, and a Dell U2412M. I tried both. The Dell works in the mini display port with no problems.

No drivers. Didn't know I needed them. Also, the DVI was working fine in a dual display setup last week and the DVI then stopped working.

OS is the latest supported by 1,1. 10.6 or 10.7... Lion I believe.
 
Interesting update. Today I swapped video cards and installed this gt120 into a different Mac Pro.

It supports 2 x monitors on the other Mac Pro. So it appears the video card is not the problem.

I also noticed the aux out jack in the back is causing some buzzing noise when plugged into a speaker.

I'm guessing there is a power issue on this Mac Pro. Maybe something got fried over the years?

Any chance this could be a software issue? I'm thinking its time to sell this Mac and find another old Mac Pro for my garage (unless I can figure out the issue).
 
Was the new one you tried a 1,1 or a 3,1 or later?

I am noticing that the "self init" behavior of some older cards is being allowed to not work as well as it did.
 
The other Mac Pro was a 5,1. So GT120's can have issues in the older 1,1's? That's normal?
 
Try putting it on a different PCI-Express port. The Mac will complain about the ports not being optimal, but all functionality should be there.
 
Try putting it on a different PCI-Express port. The Mac will complain about the ports not being optimal, but all functionality should be there.

Slot 2 doesn't work! Hmm I'll try 3 and 4.

Edit : no luck on any of the slots. I did get the warning, but can only get display out of the mini display port!
 
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I picked up a cheap $40 GT120 on Craigslist to test but wont have it until Tuesday.

I'm guessing it may work, but will probably fail soon thereafter.

This video card that is in my 1,1 did properly run 2 displays for a few days before the DVI stopped working.

In the meantime, I'm going to go looking for a cheap 2009-2010 cMP.
 
The other Mac Pro was a 5,1. So GT120's can have issues in the older 1,1's? That's normal?

Yeah, been trying to point this out but getting lost in the noise. The older self init cards seem to be losing some functions. When you use an Apple GT 120 in a 1,1 it is self init, in a 3,1 or later it is EFI.

There are EFI GT120s (our rom) but none have MDP port as there is no output display for DP in EFI32.
 
Yeah, been trying to point this out but getting lost in the noise. The older self init cards seem to be losing some functions. When you use an Apple GT 120 in a 1,1 it is self init, in a 3,1 or later it is EFI.

There are EFI GT120s (our rom) but none have MDP port as there is no output display for DP in EFI32.

Thanks for the clarification. I think I understand.

My temporary solution is to use my second GT120 (in the mail) to power the second monitor. But I think I want to keep an eye out for a cheap 2009+ MP. Got outbid on a 2009 MP 2.9ghz 8-core beast last night.
 
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