Power mac g5 boots up to desktop then screen goes completely black

[thesteakguy120]

just like the title said, previously I was able to use the desktop environment for a little bit before everything on the screen goes black, before the entire system freezes, any clue why this happened?
the Power Mac is a 2004 dual G5 1.8 GHZ pci-x model with ~5.5 gigs of ram.

 

[Unknown_K]

I have a G5 that would freeze after a short time and the screen was still visible but frozen, was the video card (GeForce 6800 I believe).

 

[thesteakguy120]

I have a G5 that would freeze after a short time and the screen was still visible but frozen, was the video card (GeForce 6800 I believe).

so, you're saying the video card that caused your G5 to freeze?

 

[Unknown_K]

Yes, replaced the card and all is fine. Still have the card probably a broken capacitor or something easy to fix just never got around to it (has a flashed 7800 in it now I believe).

But like I said the video would freeze (no mouse movement or anything) not go black.

 

[thesteakguy120]

Yes, replaced the card and all is fine. Still have the card probably a broken capacitor or something easy to fix just never got around to it (has a flashed 7800 in it now I believe).

But like I said the video would freeze (no mouse movement or anything) not go black.

I'm starting to think that might be the case with mine, I checked and it's got a geforce fx 5200, and when I reseated it, the system actually played the intro video before going dark again, so I might have to find or buy a different card to actually see if that's the case.

 

[Byrd]

Try booting in safe mode which disables some GPU acceleration - hold down shift at startup. Also resetting the PRAM and nvram might help.

 

[thesteakguy120]

Try booting in safe mode which disables some GPU acceleration - hold down shift at startup. Also resetting the PRAM and nvram might help.

I did reset the pram and nvram, I tried starting in safe mode which got me a grey screen with a blinking cursor before it froze.

 

[Byrd]

Could well be something else; clean it up (contacts, dust) strip down to a pair of known good working RAM, check for any diagnostic LEDs on the motherboard. Can you boot off other media, or DVD?

 

[thesteakguy120]

Could well be something else; clean it up (contacts, dust) strip down to a pair of known good working RAM, check for any diagnostic LEDs on the motherboard. Can you boot off other media, or DVD?

Redid the ram to just be two 1 gig sticks, no led light up on motherboard, and I have been unable to get the system to boot off of dvd or cd, even using open firmware

 

[thesteakguy120]

If you're still interested in this thread, I have a fairly small update, after letting it sit for a few days, I came back, and it boot and actually ran through the 'first start' video for OS X, but I noted some abnormalities, the fan sat at a fairly high rpm, and only ramped up throughout the video, and once it got to the point where you're supposed to input your information, the fans reached top speed and the system froze, any clue of what could be happening based on these findings?

 

[Byrd]

Lots of things!

I'd run the G5 Apple Hardware Test DVD - see if you can boot from it first.

https://macintoshgarden.org/apps/apple-hardware-test-powermac-g5

 

[thesteakguy120]

Welp, after trying to get it to boot, both on the original, and another dvd drive I pulled from my g4 mdd, I have been unable to get the g5 to boot off of the disc, I think this is gonna end up being a project I put on the back burner for a while because I do not feel like try to wrangle the cpu cards out to check to see if they're good right now, nor do I currently have the means to get spare parts to test with either.

The results of me trying to boot the Mac from the disk is just a black screen after the apple loading screen concludes, not even the fans ramping up this time.

Thank you for your help, but until I can scrounge up the money for some spare parts to test with, this likely isn't going anywhere anytime soon