Bootcamp gaming - slowdown near start

[Hejhox]

Hi - longtime lurker, first time poster here.

Tried looking around for a solution to a problem I've had but found nothing yet.

The problem I've had for a while is that when gaming in Bootcamp - talking mainly about Team Fortress 2 and Left 4 Dead 2 (although I've had the problem with Half Life 2 and Modern Warfare) is that the game plays fine for the first 5 minutes or so (around 50 fps), and then has horrible slowdown (fps down to 10-15). This sometimes goes away on its own (after about 5 minutes again) or for some reason alt+tab back into Windows for a bit and then going back in game cures it. If I can get past this initial blip the game is totally fine for the rest of the duration.

I've tried tinkering with AVG to ignore a certain steam log file as well as closing it completely but that doesn't seem to have much effect.

Appreciate any ideas.

 

[Vayner]

I have the exact same problem. It doesn't matter which game it seems.
This is also with Steam under bootcamp on Win 7.
It'll happen with L4D, Osmos, Trine,..

 

[Vayner]

Anybody an idea?
I think it may be some processor or power option, but past experiences with windows make me a little hesitant to go poke around willy nilly.

The games works fine for about 5 minutes, till the fans start kicking in. Then everything slows down to about half the FPS it was. Restarting the game while the fans are still spinning will result in a proper session.

 

[imassents]

It's to do with the GPU. As it is sharing memory with the CPU it is will slow down once it's allotted amount fills up. Your computer and graphics has only one pool of memory with one gate for entry and exit. If the CPU needs to store something, the GPU will have to wait.

Dedicated graphics have a separate pool of memory to use, hence do not suffer in the same way.

To see what I mean, lower the details of your game to as low as possible (resolution and textures). It should take longer for the slow down to happen.

 

[Vayner]

But how come it eventually works, even with high settings?
Is there a way to put the computer in the state its in after the slowdown, before you even start the game?

Cheers.

 

[Vayner]

Anybody have any ideas?

 

[Hmac]

Would that be less of a problem under the 64-bit version of Windows 7?

Might this also be heat related? I noticed I actually had a thermal shutdown last night about 20 minutes into COD4.

 

[Vayner]

It may be heat related, but I wouldn't know how to test it. And once the fans are spinning and the game is restarted after the slowdown, everything runs as it should.

The suggestion made earlier that higher settings would trigger this quicker doesn't seem to check out. As it seems to be possible to run a game like L4D at high settings perfectly before and after the slowdown. And it always happens in the same spot in the game.

If I want to play any game, I need to first "warm up" the computer. I load the first level of L4D single player and as soon as I come out of the alleys the slowdown happens. Regardless of how long it takes and what happens on the way. That is when the fans start kicking in. I wait till they're at full speed and then restart the game.

The same applies to other games such as osmos, L4D2 and some other steam stuff.