Cause of no start up beep?

[carlege]

alright ive had 2 motherboards from Asus both a8n-sli and i keep getting the same results. no beep on start up. no monitor screen. i dont even get any beeps when the memory is taken out. no nothing. all my parts work on my friends computer.. cpu, memory, videocard, but im at a loss for what to do. any help would be appreciated.

system specs
AMD 939 3200+
vga 6800 gs videocard
512 ultra 3200 overclocking ram
80 gig hitachi hd
ultra x infinity 500w power supply.

 

[JKnPA]

Remove mobo from case. Place on anti-static bag and power-on with 'barebone' parts.
Verify your 'case speaker' is connected to the proper pins, also your other front panel parts.

 

[carlege]

fixed it... the cause was a problematic Power supply ... kinda dosent make sense but the power supply powered up the MB but didnt let it boot