Need suggestions for upgrading !!

[wooshlinker]

Hey everyone this is my first post here so her it goes .
I bought this new pc a couple months ago ..

AMD Athlon II X4 620 2.61 Ghz
Windows XP srvcpk2
Mother Board ASRock N68-S
3.50 Gb RAM
NVidia GeForce 9300 GS
HD WDC WD5000AAKS-00V1A0 500Gb

...but now i realized that this is not enough to run the games i play at decent settings ... so i tried overclocking and that helped, still wasn't enough and my Temperatures went sky high .
So my question is what kind of hardware upgrade would bring me the maximum performance for an affordable price .
Oh by the way the game im trying to run is ARMA 2 and Call of Duty WaW .

I really appreciate your help .

[Aaron_8015]

Your Graphics is really letting you down.... Can you post the PSU specs (make, model, watts and +12v amps). Also your budget.

Welcome to TechIMO.

[wooshlinker]

Your Graphics is really letting you down.... Can you post the PSU specs (make, model, watts and +12v amps). Also your budget.

Welcome to TechIMO.

Foxtech 500W-TV2 +12.0 v =18.0a, max output 500w
budget up to U$ 800,00

[JPMiller]

I'm assuming you mean $800?
Is that American or what?
What online retailers are you able to use?
Are you capable/willing to upgrade this yourself?

[wooshlinker]

Yes i have up to $800 U.S to spend but i dont mind if i can do it for cheaper .
Regarding the online retailers ill be honest im not used to them so im open to suggestions and in that note i dont think i have the knowledge or skills to upgrade it myself, ill probably have to find someone to do it for me .

[JPMiller]

Well if it were me and I had $800 to play with I'd be looking at a i5 and a 5xxx series ATI card as well as a new PSU