Wow really..?

I still lag from time to time in this game. How come i can play CSS on MAXED OUT GRAPHICS (no lag!) with 200+ FPS but on this game its 60FPS - 120FPS, with lag? Really Z8 games..?

PC spec

HP-Pavilion
Processor:AMD Phenom(tm) II X4 910 Processor (4 CPUs), ~2.6GHz
Memory:8192MB RAM
Hard Drive:986 GB
Video Card: Geforce 9800+ GTX (overclocked)
Operating System:Windows 7 Home Premium 64-bit
Motherboard: DDR 3

http://www.xfire.com/profile/qsl1ckp/ (it says the graphics card is ATI Radeon HD 4350, but i recently got a new graphics card)

yea... im still lagging on smoke grenades, and just randomly lagging.

Games I play on max settings with no lag (trying to name the good looking games):
Trackmania Nations Forever
CSS
Left 4 Dead 2
Portal
Half Life 2 +
Combat Arms

And lots more


Please fix your game Z8?