FPS fluctuations

[jmartis]

I sometimes get weird FPS fluctuations when standing still in a game (so the 3D environment change is negligible). I'm playing Trackmania if that is important.

What happens is that the FPS is e.g. at 140 then it sags to 100 for a second and back to 140. Sometimes it does this nearly all the time, sometimes it happens just rarely. The FPS sag is quite noticable when playing a game.

Anyone knows how to fix this?

Running WXP Pro, 8800GT with the latest drivers (177?)

 

[JackyBoy]

Does this happen just in trackmania or does it happen in all the games you play?

 

[jmartis]

Does this happen just in trackmania or does it happen in all the games you play?

I'll try that tomorrow, TM is the only game I installed on the new system so far. But I believe I saw it in 3DMark 06 too.

 

[JackyBoy]

Yeah, have a little test, becuase i havent played TM before, but it might not be optimised well or something, so even though you cant see anything moving, it might still be rendering it behind the scenes. So your graphics card will be unnessasarily rendering things that you cant see

 

[k4p84]

.

If its a new build/install make sure all the drivers are up to date.

Pop fraps on and see what the actual fps change is

ED

 

[jmartis]

Pop fraps on and see what the actual fps change is

ED

Thats what I did. It wents from 140 to ~105, "warbles" around a bit for 2 seconds then shoots back to normal.

I've seen this problem on my old PC too but there it was quite periodical (=predictable when the next sag happens) and was caused by some windows service IIRC, while on the new build it sags quite randomly...

 

[k4p84]

140 fps to 100 fps. for a game to seem smooth 60 fps is the target so if your getting 100-140 you shouldn't notice.

unless you have fraps on...

 

[jmartis]

140 fps to 100 fps. for a game to seem smooth 60 fps is the target so if your getting 100-140 you shouldn't notice.

unless you have fraps on...

yes but it also jumps to 60 from 80, to 30 from 40 etc. It seems like some percentage of "computing power" is removed during the sags.

 

[k4p84]

.

You will never get a constant 100, 80, 60, etc fps. It fluctuates depending on what needs to be rendered at that time mate.

The harder the environment you are in the lower the fps etc.

If you have a benching tool run it through like 4 times and not fps at certain events, they will usually stay fairly similar.

If you alter the settings, lower res, etc you will see an fps gain.

If they are all over the place, i meant that, not just a few fps then you may have some hard/software issues buddy

ED

 

[jmartis]

You will never get a constant 100, 80, 60, etc fps. It fluctuates depending on what needs to be rendered at that time mate.

ED

Look at my first post, I stand still in the game so the 3D scene remains more-or-less the same, but FPS jumps. Sometimes its good for several minutes, then it will jump for a few minutes etc. It seems quite random.

 

[jmartis]

I think I got it! It was the Avast antivirus, after uninstalling it I haven't seen a single sag.

I'll write back if I see one but I think its OK.

 

[JN]

I think I got it! It was the Avast antivirus, after uninstalling it I haven't seen a single sag.

I'll write back if I see one but I think its OK.

Give NOD32 a go if you've deffo nailed it down to Avast. Its one of the better/best AV's for low resource consumption.

 

[jmartis]

Give NOD32 a go if you've deffo nailed it down to Avast.

Nope I haven't. It seemed OK for really long while but then started again, while I disabled everything (antivirus/firewall/internet connection and any other running apps). I don't get it, sometimes it will run fine for several minutes, but when I restart the game/PC it does it again.. totally weird

 

[JN]

Just a shot in the dark, but the card isn't overheating at all is it? Could attribute to a drop in FPS, but I would have thought it would go from 100fps to lag-city-fps rather than what you are seeing.

 

[jmartis]

Just a shot in the dark, but the card isn't overheating at all is it? Could attribute to a drop in FPS, but I would have thought it would go from 100fps to lag-city-fps rather than what you are seeing.

I'm sure the card is fine, ~50C idle and max 65C load gpu temps. It has nice big two-slot Asus round sink.

 

[jmartis]

I made a crappy vid with the fps:

http://www.youtube.com/watch?v=bSvnPa48lbg

(note: I'm still in the game and the 3D scene does not change)

 

[darkorb]

that happened to me with my single core 3500+ and my 6800GT. What happened was anti virus came on, or some other windows app was taking 100% of my cpu every 5-10 seconds.

Sicne u have a dual core, that sh0ouldnt matter though..

 

[jmartis]

Cannot this be because of defective video card (non-functional shaders, memory chips etc.)?

 

[k4p84]

.

i think those would manifest with blue screens and artifacts.

have you checked if another app is resource hogging ?

 

[jmartis]

i think those would manifest with blue screens and artifacts.

have you checked if another app is resource hogging ?

When idle the CPU load is at 0% most of the time and just rarely jumps to 2%. I don't know if an app hogs resources while running the game, but otherwise there is nothing eating the CPU power.

I meant my question in a way if the card finds some defective "unit", it might "skip" it and drop a frame, while still continuing to render other frames.

I tried disabling as much processes as possible, sometimes it will run fine for several minutes, but for example minimising and maximising the game can trigger the dropouts, as well as system restart. I hate this kind of subtle errors

EDIT: I also should note that the sags do NOT happen in main-menu where there is 3D sphere being rendered on the background, but only in the main 3D environment.