Celerons are P3 and P4 cpus which have half, and sometimes less, the the onboard cache of thier big brothers.
You should notice the differance between a PIII 1000 and a Celeron 2.4 if not just from the increase in FrontSideBus speed. A P3 had 256 onboard cache and a FSB of 133 as opposed to the celeron 2.5 onboard cache of 128 and quad pumped FSB of 100x4.
The celeron would use DDR ram as well as opposed to the P3's sdram.
If you need it for games you will want a P4, if it is just for basic use, a celeron will fit the bill just fine.
My $.02.
:wave: