why getting unstable performace from my pc

[bhagatpuneet786]

i just previously build up pc from trash. specs are-
core2duo
asus p5w dh deluxe
3gb ram 1*3 sticks
500gb hard disk
after starting pc when i started opening some basic programs, in the task manager the performance of memory and cpu increases dramatically, and after that my pc get hanged and im not able to use it, it just get fully stuck.
after leaving it for some time it will get normal but in that time the performance of pc also increases in between highly...
please try to solve my problem...

 

[Supahos]

Was the copy of Windows installed specifically on that motheboard or brought over from a different computer?

 

[guanyu210379]

I hope you installed the OS from scratch.
If not do so.

 

[bhagatpuneet786]

Was the copy of Windows installed specifically on that motheboard or brought over from a different computer?

i got copy of windows 7 from my friend

 

[Supahos]

Did you install it fresh on the 500 gb drive with it completely empty? Or was it already on the drive

 

[bhagatpuneet786]

Did you install it fresh on the 500 gb drive with it completely empty? Or was it already on the drive

i installed it on a 500gb hard drive which is full of crap but when i installed a fresh os of windows7 on it, then i delete all the stuff and make new partitions. but after its installation i again has to format it using quic format (i dont know why).

today i have cleaned my cpu and side heatsink also and i found that it has cockroach under that side heatsink.

i have applied new paste on it.