Folding Forum

Hi. (first time poster here)
Before talking about the problem I should say that I've done a lot of Google research before asking for help here, but none of them helped.
So Here's the problem
My PC configuration is: a Geforce 9800 GT graphics card (with the latest 300 driver) + Intel Core i7 920 + 3 GB of RAM + v7 of the FAH software
I have absolutely no problem running the SMP client, but when I use the GPU client, almost every visual activity on my computer slows down considerably (videos become uplayable)
I know that CPU clients use the lowest possible priority and don't get in the way of other applications. However, this doesn't seem to the case with the GPU client.
So can any one help me? I'll provide more information if necessary.

Yes that is a problem with the GPU client. The GPU has no priority scheduler so it doesn't see priorities like CPUs. It is known to happen, mine does that too.
Actually there's a thread about this in the forum. Try searching for it
Edit: never mind I searched it for you viewtopic.php?f=75&t=21539

Iceman's right, it is a problem. My workaround is simply to pause the gpu client when I'm at the computer. The only problem is it took a while for me to be able to remember to unpause it when I'm done. My computer at my office - 9800 gt - gets about 16 hours of gpu folding a day this way and has no problem bringing in wu's well ahead of the deadlines. My home computer, with a better card, only needs to be paused when I'm doing something demanding.

Hi there mozzalex, welcome to the Folding@home support forum!

There's already talk about a screensaver for the GPU client, which would avoid the lag problems. See viewtopic.php?f=67&t=21504#p215041 I don't have lag issues as bad as yours, but they are noticeable sometimes nevertheless. I've heard that making sure Aero is enabled helps with the problem. If you can't stand the lag, you can disable GPU folding entirely. Turn V7 to Advanced mode (drop down menu in upper right hand corner), right click on the GPU folding slot and click Finish. After the WU finishs its computations and is uploaded, that slot will shut down. Then go into Configure -> Slots and remove the GPU slot. I'm all for GPU folding, and Dr. Pande would like to see more of them running Folding@home, but there comes a certain point when the PPD and scientific gains don't make up for the system impact. Until a screensaver is released or there's some other big step taken, I think this will continue to be a problem. It's entirely your choice as to which way you want to go.

Folding on SMP with 7 (real and virtual) cores instead all 8 would give more CPU resources to the GPU, potentially reducing the lag on your system. Doesn't hurt to try it. You can always go back to 8.

But odd thread counts often lead to errors with SMP WUs

toTOW wrote:But odd thread counts often lead to errors with SMP WUs

Really? I thought it was "large primes" but last I heard from Bruce, "large" has never really been defined. Probably like 7 or 11, but that's a guess. Isn't it rather rare to have issues from core counts like that anyway?

smp 7 is a "sometimes" leads to errors, not so much an "often" leads to errors.

But yes, it can, on a couple recent projects.

Thanks all for your responses. I think I will stick with the SMP until there's a solution for the GPU client.

I am now having this issue as well. Only, before yesterday I was using the GeForce v256.nn drivers, & while it happened a bit, it was rare that I had to shut it down to do anything. Yesterday, I updated my drivers & have come up to 301.42, & I cannot use Firefox without getting 5 second plus lag on the screen. Other stuff isn't quite so bad. Other browsers are affected as well, (IE, Chrome), but not quite as much.

Have you tried disabling hardware acceleration in those browsers (or whatever the browsers call it)? I saw major lag in Opera and IE9 when it was on, but it's significantly better with it off.

There used to be a setting somewhere in FireFox which allowed you to disable GPU screen acceleration. The GPU has no priority system so F@h can hog the GPU for long enough while FF has to wait that you notice it. Using the CPU to do the same work can interrupt whatever else is going on and refresh the screen sooner.

gwildperson wrote:There used to be a setting somewhere in FireFox which allowed you to disable GPU screen acceleration. The GPU has no priority system so F@h can hog the GPU for long enough while FF has to wait that you notice it. Using the CPU to do the same work can interrupt whatever else is going on and refresh the screen sooner.

This (along with the use of an aero theme) solves my issues with the GPU client almost completely! It's really easy to do, just do what they say in this link:

http://blog.acsystem.sk/windows-7/how-d ... ion-in-ie9

This happens with my computer too, but only while browsing. Games, even graphic-intense ones, run normally. The following workaround was successful for me for web browsing: I use Firefox. Go to options, advanced, uncheck the box enable hardware acceleration. Now I can browse normally with Firefox without pausing the client. I use GeForce 560, overclocked 15%. I think this only works with Firefox, though. I still cannot use Chrome, and I never tried IE, because I never use it anyway.

mozzalex wrote:Thanks all for your responses. I think I will stick with the SMP until there's a solution for the GPU client.

I don't think there will be a solution (except the screen saver) any time soon. The gpu needs an OS to be used for any things other than FIFO.