Celeron is a very fine cpu for what you do. It sounds like the person who told you it was dodgy was a gamer. Therefore, no need whatsoever to change your processor. If you can post the model of your motherboard. Let me make some further suggestions: 1. Run chkdsk. 2. Run a harddrive diagnostics. Western Digital, Seagate, etc. all offer a free diagnostics utility. 3. Attach more minidumps.