Problem with FPS

[Giorgos_1]

Hello community , i am facing some problems during gaming

I have :

Ram : 8,00GB Dual-Channel DDR3 @ 668MHz (9-9-9-24) (1337)
CPU : AMD Phenom II X6 1050T , Thuban 45nm Technology
Motherboard : ASUSTeK Computer INC. M4A87TD (AM3)
Graphics : 1024MB ATI AMD Radeon HD 5670
SSD + 1T hardisc
Tempratures always low

While playing games i got for example 150 fps (counterstrike example) on low resolution
If i got facebook opened on chrome my fps drop at 100 , on both occasions are low

CPU usage is 25% and ram usage no more than 40% , why i facing this problem ? anyone have a solution to my problem ? should i buy a new graphic card ? faster rams? what should i do ?

Thanks in advance

 

[Giorgos_1]

When i play on worse pc than mine i got stable 300 fps with chrome opened :S