Gtx 460 sli problems. PLEASE HELP... battlefield 3

[He_Laughs]

I am using a gtx 460 sli setup. and im having a *** ton of problems. Bad frame rate, green and blue flickers. When I run each card individually, I can run the game with medium/high settings with a solid frame rate. When I run sli, it's. straight hell. I used GPU Z to check out what was happening and I saw when one card is running at 700 MHz, the other would drop to 50MHz. : (. I tried to use ntune to overclock them both to 700, that didn't work. And my PSU is a 750 watt, so that's not the issue.

I would appreciate any help, recommendations, or explanations people!
Thanks.


oh, and my setup is

Q9450
6 GB DDr2
750 watt PSU
GTX 460 SLI
nforce 560i mobo

nothing overclocked.

 

[blade061188]

When you run both cards individually, are you using them in the same slot? (PCIe 1 most likely) you could have a bad second PCIe slot for the SLI.

Also, do you have a different SLI bridge you can try out?

 

[inzone]

How many x16 slots do you have on that MB because if the second one is bad you can skip the second one try another one if you had it.

 

[He_Laughs]

I believe when you use both slots simultaneously, my mobo reduces both slots to x8. i didn't think that would be any problem though. when i use one card at a time, i only get a picture with one of the slots, if i use the other one, nothing. But in sli, my pc recognized that both slots are being used. I have two 9800 GT's lying around, so i'll do a little fiddling with different slots and different cards when i get home.

I hate when this kinda *** happens. I just want to enjoy the game.

 

[blade061188]

Yea, try placing one GPU in the second slot, and nothing in the first slot.

x8 performance wouldn't be the cause of the problems you are having. It could be a bad PCIe slot, even if it is detected. It could be partially bad, able to detect the card but not properly send information to and from the card.

Could also be the power connectors to your second card. You could try different power connectors to the GPU to see how that goes too.

 

[subasteve5800]

Are you sure your mobo is splitting the PCI-e slots 8x/8x? Some older or cheaper mobo's will split them 16x/4x. So your second card could be getting bottle-necked.

My only other thought is that if you have a really off-brand PSU it could be putting out less power than its rating. Although a 460 SLI should only consume about 500w your PSU would have to be really off-brand.

 

[Djentleman]

Are you sure your mobo is splitting the PCI-e slots 8x/8x? Some older or cheaper mobo's will split them 16x/4x. So your second card could be getting bottle-necked.

My only other thought is that if you have a really off-brand PSU it could be putting out less power than its rating. Although a 460 SLI should only consume about 500w your PSU would have to be really off-brand.

Nobody has seen a huge performance decrease with x4 bandwith..... Even with high end cards such as the 6990 - the performance decrease was only 5%. So with a mid-ranged card such as his, it is irrelevant to even bring it up.

The bad Pcie slot should be taken into some consideration though.