Tried to start up my old pc....no boot screen

[archenstone]

Hi, I tried to set up my old pc for my son now that I have the peripherals he needed to use it. Only now, it does not even show bios.

specs
athlon xp 3200
Asus a7v400-mx
2gbs pc3200 [2x1gb]
500W psu [tested working]
xfx agp card [don't remember model]

What I've done so far
checked the system with a known working monitor [no response]
    tried this with agp card and onboard video
checked all connections to make sure I had them in all the way
 removed everything till it was just the psu,mobo,cpu left

What happens
When the power button is hit the mobo light and cpu fan start up. No boot information pops on screen. Monitor acts as if no signal. Keyboard lights flash in response to start up. No onboard beebs. I'm not sure if onboard speaker is enabled....

possibly relevant;
  Computer was in 100% working condition till I stored it in april of 2009
  The only new equipment added after are 2 ide HDs and a different PSU. Everything else is untouched

[patio]

Remove all HDD's and see if it will at least POST...
Also try swapping in another known good PSU.

[Geek-9pm]

When a PC is in storage for awhile, oxide can build up on some connectors.
Also, some boards work loose for various reasons.
Check all connections and PCI and AGP and Memory cards.
Keyboard lights indicate that it is mostly working.

[archenstone]

thank you for your replies. As I mentioned in my earlier post, I removed all hardware. That includes the hard dives as well. Since I had to put everything back in after that did not work...it gave me a chance to double check my connections.

so if the keyboard lights up...does that mean I should have at least a boot screen?