Is This Typical GPU Failure ?

[mmartell]

Re: Is This Typical GPU Failure ?

I procured another 1GB stick this evening and symptoms are identical. Same on screen artifacts and lots of errors in Memtest.

[mmartell]

Re: Is This Typical GPU Failure ?

Good chance of being fractured solder joints, if you can't detect bad caps.

Yes but it's a pretty big board lol. And of course once it's installed you have very limited access to the front side and NONE to the backside which is actually the top side.

[mmartell]

Re: Is This Typical GPU Failure ?

Yeah, I forgot about that. If it has onboard graphics it's using the ram as vram.

It's not onboard, it's replaceable but prohibitive and has dedicated ram.

[RJARRRPCGP]

Re: Is This Typical GPU Failure ?

Good chance of being fractured solder joints, if you can't detect bad caps.

[mmartell]

Re: Is This Typical GPU Failure ?

The memory errors strike me as a false positive only because it would seem rare for BOTH to fail before the owner says to himself "hmm there seems to be a problem here." But I will try to find another stick or even a device to swap this ram into to rule out first.

[Th3_uN1Qu3]

Re: Is This Typical GPU Failure ?

If the memory tests bad with Memtest then definitely replace that first. See where that gets you. Though i have to say that pattern looks more like a GPU than a memory failure.

[SteveNielsen]

Re: Is This Typical GPU Failure ?

Even if it isn't check it because it threw up errors in the iMac.

[reaper57]

Re: Is This Typical GPU Failure ?

I would test the RAM in another computer.

Yeah, I forgot about that. If it has onboard graphics it's using the ram as vram.

[SteveNielsen]

Re: Is This Typical GPU Failure ?

I would test the RAM in another computer.

[reaper57]

Re: Is This Typical GPU Failure ?

Looks like the gpu. Check the caps and when you are sure they are good, install windows, but leave the video drivers for last. If it gives you a BSOD, when you are installing them, then it's probably the gpu.

[mmartell]

Neighbour gave me an iMac Core 2 Duo White gratis which was basically stuck at Apple logo which would eventually disappear leaving a white screen. The white screen has a type of herringbone pattern in it while the Apple which is overlayed seems proper.

After fiddling some this unit seems to have multiple issues which doesn't sit right. The hard drive spins but system will not boot to any OS that is presumably on it. The dvd rom makes some god awful noises but will boot Win7 installation disk and Memtest disc but not the OSX Leopard that came with it. The aforementioned discs have video errors and Memtest indicates errors on both 512MB sticks.

The power supply looked good as did the caps on the logic board which were removed for a solid cleaning.

If I were to guess I would say there are some bad caps on the MB at minimum. What you think ?