I'm planning to upgrqade my Dell Dimension 4400's processor. I'm currently using Pentium 4 Williamette 1.6 ghz, 400 mhz FSB, L2 cache 256 kb, socket 478. I've read from this forum that the highest processor that I could have would be Pentium 4 Nothwood 2.8 ghz, 400 mhz, socket 478. I just bought a Pentium 4 2.6 ghz, 400 mhz, L2 cache 512 kb, socket 478. But since it is still being shipped to our place, I forgot to check if it's a Northwood or not. I've heard that upgrading the BIOS is a risky and quite delicate process. Is it necessary for me to flash the BIOS? My mobo is D845PT with a chipsrt tha's i845D and a BIOS version of A04. Does this version supports a Pentium 4 2.6 ghz? Thanks in advance.