The Intel website has some information on what processors this board can natively support, see http://support.intel.com/support/motherboards/desktop/sr440bx/sr_proc.htm . You may be able to use newer and faster PIII socket 370 processors as well, with the proper slotket. I have run coppermine PIII 700s and PIII 750s on BX motherboards using slotkets, for example. Just make sure that the slotket specifies support for the new coppermine PIIIs. Another option is to use a Powerleap adaptor, http://www.powerleap.com/PL-iP3T.html . I think that you can use this adaptor with both PIII 100 MHz bus coppermines, which go up to 1 GHz, and Taulatin Celerons, which go up to 1.4 GHz. You can buy these as a kit (adaptor and processor), or you can buy the adaptor separately from places like Lynn Computer ($55), http://www.lynncomp.com/ , and hunt up your own processor (Newegg is selling a 1.3GHz Tualatin Celeron for $38). Usually, when I've ordered just the adaptor, they've come with a fan and heatsink, but I can promise that is still the case. John Sproule ----- Original Message ----- From: "John S. Yates, Jr." <[log in to unmask]> To: <[log in to unmask]> Sent: Saturday, July 03, 2004 7:35 AM Subject: [PCBUILD] sr440bx cpu upgrade I have a pair of Intel SR440BX motherboards. I would like to upgrade their 400MHz Celeron processors. They currently have a 4S4R100A.86A.0008.P03.9902251032 BIOS. I am willing to reflash the to the P10 BIOS available on the Intel site. What I can't seem to figure out is which PIII processors will be compatible. The NOSPIN Group provides a monthly newsletter with great tips, information and ideas: NOSPIN-L, The NOSPIN Magazine Visit our web site to signup: http://freepctech.com