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Old 07-17-08, 08:36 PM   #34
Vanzagar
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Join Date: Jul 2004
Posts: 2,167
Default Re: SLI issues/concerns and stuttering (GTX 200, 8, and 9 Series)

Quote:
Originally Posted by Neospy View Post
I'll try to answer...

The stuttering is caused by non-uniform frame times. Example:
1. GPU1 gets available.
2. The game prepares frame for GPU1.
3. it takes 5ms for CPU to prepare a frame
4. GPU2 gets available.
5. The game thinks it takes (5ms) to render a frame, it updates the scene for 5ms interval.
6. The game prepares frame for GPU2.
7. it takes 50ms to render frame on GPU1.
8. GPU1 gets available.
9. The game thinks it takes (50ms) to render a frame, it updates the scene for 50ms interval.
....
As a result, you will get 2 almost identical images with little delay between them, then long delay, then another 2 almost identical images and so on.

The slower your CPU, the longer it takes to prepare a frame -> less stuttering.

So, there are 3 options to reduce stuttering:
1. Buy very very slow CPU
2. Disable AA, AF, shadows etc to make the game CPU limited
3. Enable Vsync (which doesnt work well in SLI because of lack of Triple Buffering, performance is about the same as with single card+TB)
Sorry but that makes no sense do you have any articles/data to back that up? If you limit your cpu like you suggest then you'll just create another bottleneck...
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