the awnser to the question p35 vs x38 is really really simple.
and i am going to place it like topics:
-x38 is a bit faster even for today's cpus
-> http://www.tomshardware.com/2007/09/26/intel_x38_chipset/
-x38 supports pci express 2.0
-> note that 8800 series from nvidia and HD 2900 XT from...