Gotta love that we give websites to a guy who has a broken computer!!!!!!
Anyway, its more than likely NOT the hard drive. It is more than likely your RAM.
Well obviously he wouldnt use that PC to download the RAM tester just the same way he is using another pc to post at the cafe
As for your question - You can download that product from another PC and burn it to a disk. Then put the disk in your bad PC, reboot, and run the tester. If you don't want to do the tester then you are gonna have to find out what memory type your PC takes. You can find out exactly at crucial.com, then you have to open up your PC and actually replace those memory sticks with working ones.