Graphics issue with 8800?

Sounds like a overheating card. It is probably broken.

 

If you have a Windows install, boot into it, and run an overclocking tool. Don't overclock the GPU, just set the fans higher. Play with the fan speed and see if that improves things. If you can't hear any difference between lower and higher fan settings on the GPU, this is indicative of your GPU fan being broken and needing to be replaced.

 

Have you tried to reset the PRAM yet?

I have had this problem with my 8800 but at the time it was just a part of another issue. Now I am starting to think my card is overheating/defective as well because it is still happening.

Let me tell everyone my experience talking to Apple:

First off my main problem is that I couldn't get my 8800gt to display @ 1080p resolution on a 32" Sharp TV (GP3).

Second I can't use my 2600 simultaneously (for 4 displays) unless nothing is plugged into it when booting up. Once OS X finishes booting I can go to 4 displays and it works great. But if trying to boot with anything plugged into the 2600 I get screen corruption.

So I called Apple and got shuffled around between 3 or 4 different techs until finally being transfered to a supposed "Expert". Well the expert stayed on the phone just long enough to tell me it's my TV's fault. Also the final tech didn't even know what video card I was talking about at first (some expert) considering there are only 2 for the mac pro 2.8.

So I asked her why then the resolution I want works fine on the lowly 2600 and not the 8800? All I got was sorry contact you TV manufacturer and then a case number and hang-up. Next I found a program (switchresx) which forced 1080p and it now works on my TV. However now sometimes when I reboot I get the screen corruption issues even with only 1 or two monitors plugged in. I reboot again reset PRAM and then am good until next reboot. It's too bad that the OS X doesn't handle memory a little better or I just wouldn't have to worry about rebooting at all. I run a lot of programs and eventually I get to the point of disk swapping because after a couple days X has failed to reclaim too much memory and I am forced to reboot. It sucks when your 8 gig machine starts using disk swap when your only using 2 gigs of RAM at the moment and everything else is shut down.

Sorry I am getting off topic and ranting again. Tach try to reset the PRAM on next reboot and then wait and see if the issue surfaces again. If it does contact Apple and hope you get a better final resolution than I did.

 

Screen issues Mac Pro 2008 nvidia 2008

nvidia 8800 (year 2008) ;-)

ok I have this issues:

is the graphic card broken? Or is the mainboard broken?

Any suggestions?

 

Looks like your graphics card is beginning to overheat.

 

Dead GPU. The 8800 cards were pretty much all defective. If you're still under AppleCare, get the card replaced.

 

GPU replaced

ok gpu was replaced (Apple Care)

now working without any issues

Apple Care is worth the money (2nd repair of my Mac Pro in 2.5 years)!!!!

first repair was logic board, second repair was gpu

I hope this was my last repair of my Mac Pro, because I only have 0.5 years of Apple Care.