My friend helped me build my PC, let me start off by saying i really know nothing about building a computer or about computers. Anyway, i bought a new motherboard, ram, processor and later after he built it i had this problem where my pc would not start up at all, finding out that this was due to improper installation. the repair shop fixed it and returned it to me within a day. it has now worked for about a week and now when i go to turn it on it will boot up then just shut off. Please someone help, i really want to avoid having to take it back in.