PC Problems - Freezing

[vRS]

My PC is custom built with the following specs,

• Intel Pentium Dual Core E5200 Processor
• Asus P5KPL-AM iG31 Motherboard
• OCZ ModXStream Pro 500W PSU
• 2x2GB PNY PC6400 RAM
• 1TB Samsung HD103UJ Spinpoint F1 HDD
• Windows 7 Ultimate

This was built quite a while ago and has been runnung without any problems up to now. Whenever i try to do something simple such as creating a new folder in my documents the computer freezes. The whole system doesn't freeze its just the window that i was trying to do something in. I can click on Show Desktop and open up other files and folders but that one just remains frozen.

My USB ports are also giving me some problems too. My mouse and keyboard freeze up too and stop working. The lights on both remain on and disconnecting and reconnecting doesnt make them work. I have to keep restarting the PC for them to work again.

I have reformatted the hard disk and re-installed Windows 7 so many times but i keep getting the same problems, which must mean that its the hardware that's causing it.

Can anyone recommend any good and free software that i could use and run some diagnostic tests before replacing the parts of PC one at a time?

Thanks

 

[95thrifles]

You can try memtest first, check the memory
Also try HDTune which will check your actual HDD
Try those first, after that you can run IBT and Prime95 to stress CPU, but if youre not running an OC this shouldnt be an issue

 

[vRS]

I will try those tests first and report back.

Thanks