Odd periodic framerate drops

[granny]

Hey peeps,

Having an odd problem with my work computer. It's a p4-2.4/512mb ram with an old geforce2 vidcard (i know, it's shit, it was all I could find lying around that I could sneak into a work machine). What I'm getting is a momentary "freezing" of the display/vid-system once every 1 second or so. The hitch lasts a very small but distinctly noticable time, I'd guess 0.2 sec or so.

It's most noticable when dragging anything on the desktop - dragging a window across the screen has a jerky, granular feel to it as a result. It also manifests very clearly in any kind of game and makes the framerates feel a LOT lower than in-game fps monitors would suggest. For example SWG has a built-in framerate display that shows a nice constant 29 fps (the game is capped at that) apart from the fact that once per second it drops to 2 fps momentarily.

I've updated nVidia drivers (latest WHQL certified ones), shut down all other apps & things, even tried going through the services and shutting down everything I could possibly get away with, all to no avail.

Anyone else seen anything like this before or have any suggestions as to what it could be?

 

[Xavier]

Sounds like resource sharing... If its a PCI card you might want to put it in a different slot, if it's AGP then maybe check none of the other devices are in a slow which allocates the same IRQ?

Xav

 

[granny]

Hmm, it's an AGP, I'll have a gander at the IRQs... gawd, I thought the days of having to think about IRQs was over

Thanks for the suggestion, I'll let you know if I have any joy

 

[RandomBastard]

It sounds like what happens when you use default vga drivers. You state your using latest dets (forceware now incidentally) so only think i can think of is chipset drivers prehaps?

 

[granny]

Hrmm, OK, the vidcard is sharing IRQ16 with two USB Universal Host Controllers, but how on earth do I go about changing IRQ's in winXP?

 

[Xavier]

Hrmm, OK, the vidcard is sharing IRQ16 with two USB Universal Host Controllers, but how on earth do I go about changing IRQ's in winXP?

Unless you're using them just disable them from the BIOS and plug your mouse/keyboard into the PS2's. Heh.

Xav

 

[granny]

OK this is still happening :/

I tried removing all the USB devices (liberated a PS2 mnouse & keyboard from a store cupboard) and disabling the USB controller in BIOS but it made no difference so I've plugged them all back in again.

Got any other ideas?

 

[xane]

I would suggest playing around with the BIOS settings, like "Fast AGP Writes" and the "AGP Aperture".

 

[granny]

Right, tried all the options I could find in the BIOS, there wasn't a setting for Fast AGP Writes but I did try 6 different AGP Aperture sizes, no difference at all.

I've told it to not assign IRQ's to USB, no difference.

Starting to really annoy me, maybe I'll just pour iron filings into the back of the PC and when the smoke has cleared hoover them out and say I need a new computer cos this one "just blew up for no reason!"....

 

[Doomy]

Its not CThelper.exe in the background by any chance? Creative soundcards install this and in some machine setups goes crazy once in a while and hogs resources up to 98%? Long shot but maybe.

Disabling it is perfectly safe to do so just try that.

 

[RandomBastard]

Tried cleaning the hsf out by the way? My geforce 4 started overheating during use cause there was enough dust to almost stop the fan in it (i remove most of it by hand and have an air duster to remove the rest ).