Need help on upgrading my PC

[mobbdeep856]

Here are my spec's, I don't seem to be getting the fps i want in games, WoW is about 20-60, CSS 140-200, cod4 is about 200-250, here are my spec's

GPU: EVGA GeForce GTX 260
CPU: AMD Phenom II x4 9850 quad core
RAM: WINTEC AMPX 4GB
HDD: Western Digital 160GB 7200 RPM
MOBO: JetWay AM2+/AM2 AMD 780G ATX AMD Motherboard ( I think i should upgrade this)
OS: Windows 7 Ultimate 64-bit

Yes, i DO NOT have vsync on, i adjusted all of my settings in the NVIDIA control panel, and YES i have all of my drivers up to date
Any thoughts on what i should upgrade?

[Xebec]

Your graphics card is the thing to upgrade, if you like Nvidia then get a GTX560 Ti, or GTX570. Also what PSU do you have, you may need to upgrade that for the new card as well.

[Blobman001]

hang on
why do you need to upgrade? do you wanna get 1000 fps in CSS or something?

[JudgementBullet]

hang on
why do you need to upgrade? do you wanna get 1000 fps in CSS or something?

This, unless you're planning on playing more recent games.

[mobbdeep856]

No i want a decent fps in all games, like to be able to handle crisis, black ops, etc

And another question, is it possible to SLI to different cards, lets say my gtx 260 with a gtx 460 fermi,