How much bottleneck i have?
CPU : Amd athlon x2 5000+ @ 2.8 Ghz
Graphics: GTS 450 GS GLH
Ram: 2 Gb DDR2 800
If i play Crysis ON STRONGER CPU on 1440x900 w/o AA Enthusiast, and if i have 30 fps how much will i have on my CPU???
Looking at your system, I would first look at your CPU. The Athlonx2 is an older architecture that is having a hard time keeping up with modern games. You may want to invest in a new CPU,motherboard,RAM combo(4GB+). Even if it is a Phenom II x2,Athlon II, or i3 it would do you much better. A Quad core would be preferable, Phenom II or Intel i series chip.
The GTS 450 is more of a mainstream card, so don't expect dazzling graphics even with a system upgrade, but it will perform better than what you have currently. It is a modern series of card so you should be fine.