Puzzled by games crashing when using second gfx card for PhysX

[MarcusCardiff]

Recently my 4870 X2 failed and as I had a GT240 laying around I put that in until I could get a better card. I then purchased a GTX 460 Cyclone and ran that with the GT 240 as a dedicated PhysX card.
I started up Fallout 3 and it started having random crashes on average about every 35-40 minutes. I tried New Vegas and the same thing. I had been able to run both games with almost no crashes using my 4870 X2.
I tried various drivers thinking there might be a bug but crashing continued.

The only thing I could think that was different was having a second card for PhysX, So I removed it and now both F3 and NV are running as stable as they were on my old 4870 X2 (RIP).

So my question is, why would using the 240 for PhysX cause the Fallout games to randomly crash? Hope you can help as this is really puzzling me and I am also wondering if this will happen if I use a second 460 in SLI.



Win 7 x64
Q9550
Maximus II Formula
4Gb Ram
850w PSU

 

[DustSailor]

does your motherboard support SLI, and are you installing the graphics cards in the right slots x16/x16 (see mb manual)? Have you downloaded and installed the most recent graphics card driver for your 460, and does it support the other card as well in the list of supported cards? Do both cards support physx? Have you gone into the Nvidia control panel and specifically set the correct card as physx?

I would guess your motherboard needed to support SLI before you could have Physx. I may be wrong, but it sure doesn't hurt.

 

[MarcusCardiff]

Thanks for the reply Dustsailor.
Yes, the mobo supports SLI but haven't used SLI yet. I had the cards in the correct slots. I was using the 240 to run my second monitor and I had it set up for PhysX in control panel. I used various driver versions which all suport both cards.
I also ran MSI Kombustor and the PhysX performed fine in the tests.
I also tried the games with the second monitor off as i read that can cause problems in Oblivion, but i had crashing whatever i tried until i removed the 240.

 

[stormy13]

Seeing as neither of those games use Physx, have you tried them with it disabled? The game should ignore that it is even there, but who knows.

 

[DustSailor]

Seeing as neither of those games use Physx, have you tried them with it disabled? The game should ignore that it is even there, but who knows.

I wouldn't know how none-physx games would perform with it on either; your computer does fine when not playing those games? Perhaps you have a game that uses Physx to test this theory? Your computer can play games like chess, etc?

And just to clarify, you have only installed a single driver right? You are not supposed to install 2 drivers for 2 cards, just the single driver I mentioned here
::Just to clarify, you have geforce 460 (not 460SE or notbook, right?) and geforce 240, yes? The link I gave is for 460, and it supports geforce 200 series graphics card as well, so both are covered. I recommend uninstalling all graphics utilities and software, including audio and physx, and reinstall with the link I provided

Also, your system specs on the forum suggest your graphics card is radeon. they both are Nvidia, right?

 

[MarcusCardiff]

Yes, I only used 1 driver and both cards are Nvidia, the 460 is a factory overclocked MSI and the 240 is Palit I believe.
I also did an OS reinstall so I did use all new drivers to no avail.

Seeing as neither of those games use Physx......

That's why I was so puzzled, I thought the second card was just doing PhysX and therefore would be ignored. I didn't turn off PhysX though and I don't really want to put the 240 back is as it obviously causes problems.

Maybe there's a fault in the 240 that's causing this, beats me.

 

[simmo]

the 240 shouldn't be an issue..ppl run a NV card (for Physx) and ATI cards for the display without any issues so all NV cards should be trouble free one would assume.
No point running it (physx) in those games as it's not supported so you could maybe run the card but have it disabled?...
And having 2 cards in SLI with the 240 doing the physx should also be no drama..it's being done all over so ya I fail to see why you should have issues with this.
Both games are buggy as tho so it's probably game related rather than hardware....cheers