This mainly happens in Call of Duty 4, and it's even worse in World at War, walking through a smoke grenade lowers my fps down to 10-15, from a usual 40-80. The single player mission "Burn em out" is unplayable, since there are many smoke grenades and flamethrowers, a combination of the two gives me about 4fps. I don't think this is a common problem although I've heard of a few people having the same issue.
My card is an XFX 9600gso 768MB GDDR2, and it runs pretty much all my games are maximum settings. Smoke in Left 4 Dead seems to lag me as well, but Fallout 3 and Call of Duty 2 for example, play just fine. I know in Call of Duty 4 disabling "Soften Smoke Edges" seemed to help a bit, but this option doesn't exist in World at War. Is there a workaround I could try, or should I contact XFX and try to get a replacement (which I really don't want to do since it could take months). I've tried changing Operating Systems and using different drivers, but they don't seem to change anything. Full specs listed below:
Windows XP SP3 32 bit
4GB G.Skill DDR2-800
500GB Samsung Spinpoint
XFX 9600GSO 768MB GDDR2
AMD Athlon X2 6000+ 3.1GHz
Motherboard was made by Acer (Computer used to be prebuilt until I upgraded everything besides the motherboard)
480W Sunbeam Power Supply, 18A on 12V
However as it is a pre-built can you run cpu-z and find out how many pic-e lanes you are actually using, its a long shot but it might only be 4 or 8, although 8 should be plenty, it was for my 7900GTO.
Corey, others might not be running as high a res or as much AA or some other graphical setting. there is probably a specific setting that affects smoke and fire although I wouldn't know what it's called.
And the term for graphics isn't lag, that's a networking term.
Nb. As you you say pretty much all your other games run fine, that pretty much eliminates hardware issues like overheating, inadequate power, yada yada - if it were a hardware problem, the system would crap out on any demanding 3d game.