Fixing pc...

Today I was repairing the PC of my father's friend after get off work. When I was checking the PC, it had the antivirus without updates since 3 months year ago. So, the PC was infected with a lot of viruses, trojans, worms,etc. But, It wasn't just the problem. Also, when I was turning on the pc and tried to install a program from a cd-rom, it turned off automatically and when i tried to turned on again, the PC didn't give me any answer :( So i had to open it and start to clean the pc with my vacuum and a small paintbrush 'cause it was very dirty inside and with a lot of dust. After clean it up, I made some tests to the computer and I found that the hard drive, a fan and the power box (I don't know exactly the name in English) was broken.Well... tomorrow i have to call to my dad's friend because right now it's too late and I'm tired. bye bye