Finally put in second GTX460 card, enabled SLI, now get GUI lag in Win7

[VirtualLarry]

I upgraded my pair of Q9300 rigs, and consolidated my GTX460 cards into one bigger rig, with an X6 1045T and an ASrock 990FX Extreme4.

I just finally put the second GTX460 in, installed the "2SLI" bridge, and enabled SLI mode in the NV control panel.

Now I'm getting a slight bit of GUI lag in Win7, most noticeable typing in textboxes, the letters take a split-second to appear, they aren't instant.

It's not horrible, but it's not as good as it was with a single GPU.

Has anyone else noticed this with SLI mode enabled, and crunching on the GPUs?

I'm using BOINC, with PrimeGrid configured to use NV GPUs.

 

[Ken g6]

With BOINC you shouldn't need to run in SLI mode. Unless you want it for gaming or something.

 

[ZipSpeed]

Yeah, I didn't bother with the SLI bridge on my dual GTX 460 rig. No perceivable lag either.

 

[Sunny129]

Larry, judging by your sig, it appears we're talking about your main/general use rig, not your cruncher. nevertheless, i'm sure you would have posted about your problem in the VC&G forum if you weren't planning on doing at least some crunching on this machine...after all, 2 idling GTX 460's would be a horrible waste of resources from a crunching perspective. as the others have already mentioned, X-fire isn't at all necessary for crunching. while sometimes the effect of X-fire on crunching is negligible, and even occasionally beneficial, most of the time it actually hurts crunching efficiency and increases run times (depending on the project application, as well as hardware configuration). given that this isn't your main cruncher, i'm assuming you want X-fire enabled to do some occasional gaming?

 

[VirtualLarry]

Yeah, this rig is supposed to be both a crunching rig and a gaming rig. I guess I figured that enabling SLI wouldn't hurt anything crunching-wise, but now I see that might not be true?

Edit: Just to test, I closed BOINC and switched SLI off (for some reason, it said I had to close AIM too).
I re-started BOINC, it picked up the two seperate GPUs fine, and now the GUI lag is gone.

I'm going to leave SLI off, unless I'm actually gaming, I guess.

 

[Sunny129]

Yeah, this rig is supposed to be both a crunching rig and a gaming rig. I guess I figured that enabling SLI wouldn't hurt anything crunching-wise, but now I see that might not be true?

yeah, its like i said above - once in a while SLI can have no effect on GPU crunching, even more rarely does it actually help GPU crunching, and more often than not SLI hurts GPU crunching...

I'm going to leave SLI off, unless I'm actually gaming, I guess.

enabling/disabling SLI is just a simple matter of going to the nVidia control panel, is it not? some people find even that to be too much of a PITA, but if it were my rig, i would be perfectly content to have to disable and re-enable SLI whenever its necessary.