All Pentium 4 chips now use RDRAM (slightly more expensive than it's equivalent DDR RAM). SDRAM won't work with your P4.
Your dealer is pulling a fast one. A 300W power supply will suffice unless you're planning on adding 9 SCSI 2Tb Hardrives and 4 10in fans!
You may want to take a look at this page:
Asus Man I would highly recommend his choice of motherboard.
[ 11 November 2001: Message edited by: Superpilot ]