ATI vs nvidia Folding

lordbean

Just thought I'd share some observations regarding GPU folding with the two different manufacturers. These are made using my gaming rig in my sig, and my second rig which uses a Conroe E6600 with a solo HD4850.

Observations:

nvidia: F@H executable and core do not use CPU time, only RAM and graphics power. This leaves all your cores open for the SMP folding client.
ATI: F@H core uses one of your CPU cores. On a dual core machine, this means you can only run one single-core CPU folding client with it.
nvidia: Seems to depend on what project it's working on, but the folding core tends to seriously lag even the windows desktop. Folding must be paused for timely use of the system.
ATI: Folding seems to have no impact on the windows desktop. The system is still fully usable for browsing the internet, etc.

I'm not sure whether each instance of the ATI folding client would eat another core, but I suspect the answer is yes. This means that for rigs where you want to fold using multiple GPUs, I would highly recommend nvidia. Cheapest bang for your buck folding at the moment is, I suspect, a system equipped with 2 or 3 GTX 260s.

If you want a terminal you can browse the web on and still run folding, an ATI-equipped system is the answer. It doesn't generate as many possible PPD as an nvidia system (since folding on an ATI card also uses CPU power) but the PC still appears to be fully functional outside of games.

DrLiam

Actually, I've played games with ATi F@H on and didn't notice a few times. It's exceptionally good at not interfering with your computer experience.

But like you said, if you max out the your CPU usage with desktop applications or a game then you will start to notice an annoying lag. (I do notice during video decoding.)

mas0n

Yeah, it's been a while since I had my Nvidia cards folding, but if I used to forget to disable GPU2 even to watch a full screen video it would be almost a full minute before the system would respond and I could disable it.

On my main rig with an HD 4890 I can play TF2 while folding and not drop below 60fps.

lordbean

I suspect it's due to the implementation of the CUDA vs ATI-equivalent drivers. nvidia's CUDA seems to run 100% on the graphics card and has very little interaction with the system, which apparently makes it not too good at prioritizing user experience when the user is actually at the PC. The ATI one obviously interacts with the PC more, since as I've already noted, it uses additional CPU power. I'm definitely interested to learn you can actually play games on it while folding... I hadn't tried doing that, I just assumed it wouldn't work (since the nvidia GPU2 process makes it all but impossible).

mas0n

Not all games mind you, but Source games seem to run OK albeit at a much lower frame rate than if you weren't folding. I assume this has to do with how the game engine calls upon the hardware.

lordbean

Could be, although unless I'm badly mistaken, nearly all games access the graphics hardware through DirectX or openGL, which then make calls to the installed graphics driver, so in theory it just comes down to how well the graphics driver manages the folding app and the game simultaneously.

mas0n

I'm sure the driver has much to do with it, but I would still think that some game engines would handle fighting for access better than others even if the driver is doing all the work. The whole thing is pretty amazing to me, what with the driver handling calls from 2 separate APIs simultaneously.

makoa26

I have a 384 point WU using 4.64% average CPU time according to process lasso and a 511 point WU using 3.12% average CPU time. If you set your environment variables, you can drop the GPU2 client's processor usage enough to run another client. My Q6600 @3.2 runs 2 SMP clients and my 2 4870's each run a GPU2 client. If you are interested, here is a very good thread on setting it up http://foldingforum.org/viewtopic.php?f=51&t=9162 My settings are:
BROOK_YIELD = 2
CAL_NO_FLUSH = 1
CAL_PRE_FLUSH = 1
FLUSH_INTERVAL = 144
If your clock speed and GPU are similar to mine, than my settings should be good for yours.

lordbean

The card I have in the system is a Radeon HD4850 at stock speed (625MHz GPU / 993MHz mem), with an Conroe Core 2 Duo E6600 @ 2.7GHz. CPU time is currently 50% solid by the GPU2 client. I don't know where those options go, nor does the thread you linked explain it any better.

makoa26

lordbean wrote:

The card I have in the system is a Radeon HD4850 at stock speed (625MHz GPU / 993MHz mem), with an Conroe Core 2 Duo E6600 @ 2.7GHz. CPU time is currently 50% solid by the GPU2 client. I don't know where those options go, nor does the thread you linked explain it any better.

Right click on "my computer" (just "computer" in Vista) and select "properties". Then go to Advanced System Settings. Select Environment Variables, then add the new variables and settings to the System variables entries (the lower one). Be sure to use ALL_CAPS_AND_AN_UNDERSCORE between words or just copy and paste.:bigggrin: I would probably change FLUSH_INTERVAL to 128 for your system just as a semi educated wild guess. It might use a little more CPU time, but will add a little more stability. I actually haven't EUE'd in a long while with my settings, but I'd rather give "safe" advise that works than something on the ragged edge that just works for me.

lordbean

Ok, I'll give it a shot.

Edit. That worked rather nicely, thank you. FahCore_11.exe is now using only 1% CPU time for the most part, with rare momentary spikes to 50%. I reinstalled the SMP CPU core on the system.

Snarkasm

(I have gamed with nV GPU folding running. It's all about the drivers.)

makoa26

lordbean wrote:

Ok, I'll give it a shot.

Edit. That worked rather nicely, thank you. FahCore_11.exe is now using only 1% CPU time for the most part, with rare momentary spikes to 50%. I reinstalled the SMP CPU core on the system.

Glad I could help. More PPD never hurt anyone, and more science can only help.

Garg

Nice to know there's a way to reduce CPU load, thanks makoa! The thread you linked suggests that these settings will be auto-optimized in a future release of the core, which sounds pretty awesome.

I can definitely corroborate lordbean's observations on the nVidia folding. It's kind of a pain to have to disable the folding client before I do anything (experienced this on my laptop), so when I finally upgrade the card in my main rig, I'm going to go ATI.

lordbean

Snarkasm wrote:

(I have gamed with nV GPU folding running. It's all about the drivers.)

Details would be nice... my rig isn't usable for even the desktop most of the time the nvidia folding client is running, let alone gaming...

I'm running the 190.38 drivers atm.

_k

182.06

lordbean

_k_ wrote:

182.06

Excellent suggestion, and thank you sir. 182.06 DOES seem to be compatible with folding while gaming. At least, World of warcraft isn't having any trouble, and I didn't stop either the SMP or the GPU2 clients.

_k

I just used makoa's settings and CPU usage is gone for the GPU2 client, ATI duh, and it gave me a little boost. The boost is most likely from clients not fighting over cores any more but its still good all the way around.

makoa26

_k_ wrote:

I just used makoa's settings and CPU usage is gone for the GPU2 client, ATI duh, and it gave me a little boost. The boost is most likely from clients not fighting over cores any more but its still good all the way around.

What's the specs on that rig?

_k

xp x64, AMD Phenom 9600BE 2.4GHz, and 4670.

noneuno77

i saw a video of some one with 4 nvidia480 folding and a 8core cpu. they stop the smp cpu from folding but keep the 4 video cards running. but the 8core cpu ran at 15 to 20%
the hole time the cards folded so what was that about how nividia dus not use the cpu to fold?

_k

Link the video. If they were simply showing CPU usage during that time then I call bunk.

I would expect to see usage bounce between 5-12%(S.W.A.G) from folding alone because you have to hit it from time to time.