I've having some FPS issues in WOW and TF2. I run at 1680x1050 with 2xAA and 8x AF. I will often see 20FPS in busy times, and occasionally in WOW I'll actually see stuttering because too much is happening, which just seems low for my specs (or maybe it isn't?)
Basically...where is my bottleneck, if I want to get to the next level of performance without overclocking where is a good place to start.
Do you have any non-internet connected games to use for performance testing? Are they slowing down too?
Run some hardware benchmarking programs, check temps on CPU/GPU to make sure they're not "throttling" during games.
Anything set to "000" can not be changed, i would suggest trying a latency of 32 or 64. I had a similar problem when i got my XI-FI Extreme gamer which was set with a latency of "248" and when i changed it to 32 all of my lagging/problems went away. This may or may not fix your problem but it is worth a try.
*Note. Some motherboards let you set the PCI latency in the Bios.
I bet it is your internet connection or server the game is on....I have dsl at 3 mbps and I have stuttering also occationally but I know it isn't my system! Intel core I7 920, 6 gigs corsair dominator, 1 tb wd caviar and a gtx 295, and a samsung 2493 HM monitor running 1920x1200