Constant lock up/freezing

[MrSmoke]

First off, if this is in the wrong section i apologize.

I am experiencing issues with my PC and can't seem to find any solutions which are fixing the problem. I am getting random freezing with my machine. Its a custom build i recently purchased used.

It had Windows 10 on it but i switched it back to Windows 7 as i prefer that much more.

Reinstalled all the necessary drivers directly from the manufacturers websites. Installed Steam so i could do some light gaming with a friend of mine, and thats when i started experiencing my freezing. Its not limited to just when im trying to game though. Its completely random.

Some details.....
ASUS PH861-M LE/CSM MoBo
AMD HD 6900 GPU
i3 2120 CPU
2x 2 GB DDR3 dual speed RAM
Antec 380W PSU

Currently i am in the process of doing a system restore to last week just after i installed Windows and updated with SP1 in hopes that will help.

Any help, insight or suggestions are greatly appreciated.

 

[hang-the-9]

Did you check temperatures? Try running with one RAM stick at a time? You said you already did a clean Windows setup correct? Check for hard drive errors? Make sure video card and power supply are working? Used system, it may have had issues to begin with that cause this, which is why it was sold. Can be a hardware issue.