Quote Originally Posted by cadaveca View Post
becuase the cpu goes idle waiting for vgas..this "lapse" while cpu is idle, then loaded, leaves spurts of traffic over the pci-e bus, causing stutter as data from the cpu slows the data flowing in the card out to monitor.


Luka, just check out the slide pics in this very thread about microstutter...it's shown there too.


this is not the only cause of microstutter, but it's definately an issue.



Phenom isn't too bad...it could use 3.2-3.4ghz and a slightly faster bus. Core2 @ 3.0-3.2 400mhz FSB or higher is ideal.



Remember boys, I'ver got dual 3870x2's...I'm dealing with the issue on a daily basis. I've almost completely eliminated the problem...some apps are more prone to it than others though.


It's a problem with memory control...within the vga. vga gets data from cpu, it must buffer the data...no data, it works only on data available, and will use as much of the ringbus as possible.

Cpu sends some data down....it goes on the ringbus too...but now it interferes with rendering as the dispatch controller must deal with pixels in flight, and pixels data incoming.
So we need more efficient and wider bus-interfaces, so data can flow and not stutter.

Nehalem should bring that along with triple channel, shouldn't it?

But it also brings a problem, if my line of thinking is correct: internal ring-buses should also be wider, in order do deal with so much data, correct?

I mean, what advantage would be having so much bandwidth from CPU to GPU, if the GPU ring-bus isn't able to deal with so much info? Coming to think of that, it surely seems a cause to multi-gpu solutions failure, small ring buses on each gpu, do not allow them to create a fluid data path, does it?