A while back, my parents had a computer (owned for 4 years).. then towards the end of its life (under their ownership) it began to run slow and eventually refuse to boot. They turned the machine over to me and so I placed different OSs on it and discovered that they too were running slow. Next, I performed a hard drive diagnostics in the BIOS to find that the hard drive in the machine was dying. So over the summer, I went out and bought a new hard drive (HP, the computer's manufacturer said the HDD had to match exact specs or else it wouldn't function properly).. So I did that and to this day the computer is acting good as new under my ownership.