Multi GPU problem

[dr.walrus]

Right, So I've got 4 monitors, so I have two GPUs, obviously not running in crossfire.

Main - XFX Radeon 4850
Secondary - XFX Radeon 4650

I have a variety of crashing problems, which I will outline below:

1. Under 3D load, the 4850 crashes. This is most evident with UT3, but doesn't happen at all with Bioshock. Screen goes grey, vertical lines.
2. With some fullscreen video content, videos running off the 4650 crash. Sometimes the system will recover, sometimes it won't. Black screen, sound still plays, but can't get to what's on the screens.
3. Occasional (rare) random crashes. As per 2.

I know this much:

1. It's not heat. The highest temperature ecorded is when the 4850 crashes (58 degrees). The system has fans poking out of every orifice.
2. It's not power. Yes, it's only a 500w power supply but the 4650 is a low power card. Besides, the UT3 crashing still happens with only the 4850 in.

So I've got an RMA arranged for the 4850 (already established it's goosed), but could the 4650 be duff too? Anyone know of any known issues?

I could, like, not be lazy and test the two cards individually, but I have lots of deadlines looming and I really don't have the time! Anyways, it's hard living without 4 massive monitors once you're used to it.

[Luke122]

Does UT3 still crash with only the 4850 if it's in a different slot? Could it be a motherboard issue? BIOS up to date?

I've had a similar issue to #'s 1 and 2.. turned out that my motherboard was restricting my PCIE 16x slot to 4x. Stupid piece of crap.

If it happens with either card, I'd suspect mobo, but still.. PSU is possible.. depending on the age of the PSU.
And it's the cheapest thing to replace and test.

[dr.walrus]

Nah, trust me the PSU is worth double the cost of the 4650!

Yeah it'll be worth switching the two, but this happened with the 4850 well before the 4650 arrived :s

[nevermind1534]

Even good PSUs can die or be defective, even though there is a lower chance of it.

[dr.walrus]

Even good PSUs can die or be defective, even though there is a lower chance of it.

I didn't know that at all

[Kayin]

I burned up a PC Power and Cooling Silencer 750.

[haha49]

What os are you useing? because the it could be driver related since the 4800 series card and the 4600 use diffrent drivers.. I had a 4850 and 4870 and it worked fine in vista.. when I crossfired saw 10fps more then the 4870 alone.. Could also be power related but I think its most likely drivers if you useing vista (cant use 2 drivers at the same time)

[dr.walrus]

What os are you useing? because the it could be driver related since the 4800 series card and the 4600 use diffrent drivers.. I had a 4850 and 4870 and it worked fine in vista.. when I crossfired saw 10fps more then the 4870 alone.. Could also be power related but I think its most likely drivers if you useing vista (cant use 2 drivers at the same time)

They use the same drivers, file for file. And Vista CAN use two drivers - but they have to be the same vendor. I've used a variety of non-compatible drivers in the past.

Besides, it crashes with just the 4850 in, and with many versions of drivers.

It's not power related. Problems too pattern-related for that, only crashes under specific circumstances, not all load tests.

[dr.walrus]

The issues seem to be compound - particularly the crashing problem on the secondary whilst using bbc iplayer. GPU activity dropped down to 0% even whilst full screening, meaning the card isn't doing any acceleration. After a mixture of swapping slots and re-installing driver, reinstalling adobe flash player, I haven't isolated the problem but the secondary graphics card failing problem seems to have stopped, the primary GPU still crashes under 3D load in certain games.

[Luke122]

My understanding was that Flash is not GPU accelerated at this time..?