Problem with new build!

[Craftish]

I just got a SilverStone SFF case and was switching my older setup over to it today (specs below). All of the components are known to be good and worked in my old setup (obviously though I now have a microATX board). The problem is that I don't get any display when I power the system on. Everything starts up fine: HD spins up, CPU Fan is on, CD-Rom spins up, the chip even gets warm, but for some reason no display appears. Any suggestions? I've tried resetting the CMOS, unplugging nonvital components, etc., and I've tried using both the onboard graphics (my mobo has the 865g chipset) and a separate video card, both to no avail. Thanks for any help. Specs:

P4 2.8C
1 gig OCZ 3200DDR (I've tried it with just one stick in and in multiple slots)
Asus P4P800-VM
Seagate Barracuda 80 gig SATA HD
Radeon 9800 Pro (I've also tried with the onboard graphics)

Since all the components worked on my old setup, I'm inclined to blame the mobo, but any suggetsions?

 

[Chelica]

Could also be the CPU. Try using a different test CPU and see if it will boot.