I have a Compac with a Celeron 325 Prescott Socket 478 mPGA 90nm @ 2533MHz 133MHz Bus 533MHz FSB. The mother board is a Micro-Star Inernational model Gamila/Glovani/Neon 030, chipset Intel i845G rev B1, southbridge 82801DB (ICH4). The BIOS is Phoenix version 3.15 dated 08/05/2004. My question is can I upgrade the CPU to a Brand Intel Series Pentium 4 Model BX80546PG3000E CPU Socket Type Socket 478 Core Prescott Name Pentium 4 3.0E Operating Frequency 3.0GHz FSB 800MHz L1 Cache 12KB+16KB L2 Cache 1MB Process Type 90 nm 64 bit Support No Hyper-Threading Support Yes Multimedia Instruction MMX, SSE, SSE2, SSE3 Thanks for any help. The NOSPIN Group is now offering Free PC Tech support at our newest website: http://freepctech.com