anyone have a link on diagnosing these to verify this is my issue
I did run mac hw diagnostics & it found no problems?
also a link that might help step me thru finding a replacement & actually replacing this card if its my issue would be awesome.
thanks.

Longer version of whats going on:
My G5 has been starting to act up again.
Problem started 2-3 weeks back where on startup i'd get apple splash screen /
spinning bar or loading / then screen gets the fuzzies white/gray on top with black background, seems to roll down the monitor then it just shuts down

searched thru this site and removed all I/O devices except kbd & mouse. still had same problems, then Reset PRAM and this got me further
still lots of horizontal lines but I was able to bring system up and lower resolution.
now I have a semi functional machine most of the time but 800x600 stretched on this is not very fun.

still getting intermittent horizontal noise & really need to get resolution issue resolved.

any help is greatly appreciated...

system profiler info:
Machine Name: iMac G5
Machine Model: PowerMac8,1
CPU Type: PowerPC G5 (3.0)

GeForce FX 5200:

Chipset Model: GeForce FX 5200
Type: Display
Bus: AGP
Slot: AGP
VRAM (Total): 64 MB
Vendor: nVIDIA (0x10de)
Device ID: 0x0329
Revision ID: 0x00b1
ROM Revision: 2103

Left off OS details:
System Version: Mac OS X 10.4.11 (8S165)
Kernel Version: Darwin 8.11.0

Set the colors to 256 and if the problem doesn't occur, the videocard is defective.

An iMac G5 that is PowerMac8,1 would seem to be one of the earlier models, so you probably should check the boards for bulging or leaking electrolytic capacitors. To see some examples, check out:
http://www.pbase.com/flgator/imac_woes

thanks.
when I set it to 256 should I have to restart the machine?
I hadn't played with the colors really so after reading your post I did.
At the time I was able to put it to highest resolution on thousands of colors without any issues. however an hour or 2 later when 1 of the kids was on it, it started acting up & actually powering itslef down.
when I'd push power button to come back up, it would come to spinning bar then just keep shutting down.
did the PRAM reset and after 3-4 attempts was finally able to get it back up and now i have it set to highest res but 256 colors.
after seeing the other post about the capacitor issues I'm wondering if this issue may be more than 1 issue.
I'll have to pop this open & see if there are any capacitor issues.

thanks again.

I'm striking out here.
I set the colors to 256 and the computer continues to shutdown on its own.
I also opened it up and examined the capacitors and none appear to have any issues or look anything like the pictures at the site showing exploded capacitors.

Anyone have any other suggestions on next troubleshooting steps.

Thanks,
Joe

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