I'll try to make a long story short here... I was using my Mom's computer over the holidays it seemed a little slow, she said it was a custom build by the computer tech instructor about 2 years ago at the school she coordinated adult education. I ran Belarc advisor and it told me her mobo was Intel Corporation D945GCCR Belarc also said there is a Celeron 2.8 in it. Everything is stable, just as slow as that CPU is expected with lots of processes (no viruses) and I wanted to upgrade it. It was built for a 800mhz CPU but with a BIOS flash it is capable of running 6000 series core 2 duo and quad but the board was never really meant for it I expect. (Finally takes a breath and asks my original question.)Ya think I should go low level C2D or high level Pentium 4 and the obvious price difference. Any good ideas or arguements for one way vs. the other is appreciated.