the problem is the P4 m8, that cpu does generate lots of heat. you want the core duo ones, that with their power management optimized wont drive u nuts again.Wouldnt touch an AMD CPU with a barge pole but thats just personal opinion.
brands i trust in are HP and Lenovo (formerly IBM).
check out the lenovo thinkpads, they been my choice for yrs
if u want more advice PM me or msn