Intel D845WN motherboard procesor upgrade question

[Mel]

I currently have a desktop computer with a 1.80 gigahertz Intel Pentium 4 with 8 kilobyte primary memory cache and 256 kilobyte secondary memory cache installed on my Intel D845WN motherboard. I would like to upgrade the processor. My question is what is the fastest processor that will work with my current setup? I will have one of my computer builder friends install the processor but I would like the swap to be as fast and painless as possible. Any help would be much appreciated.

[random_noob]

your motherboard supports Pentium 4 processor with a system bus frequency of 400 MHz. so you need P4 with 400MHz bus speed, fastest is 2.8GHz(so say intel.com, but in cpu-world is also listed 3GHz(30x400MHz ).
D845WN- officially fastest supported processor is Pentium4 2,6GHz(http://support.intel.com/support/motherboards/desktop/d845wn/sb/cs-008944.htm) with BIOS version P12 or greater, so maybe you need upgrade your motherboard BIOS.

i know, my english is awful