Computeris not starting up! Help!

[Hydroshock]

all the devices are turning on etc. but nothing is displayed on the monitor, im sure the monitor is working and my video card is good (i tried 2 different ones). Also the HD is not booting windows (i can tell because its different from normal sounds)

 

[Yankee Rose]

Can you boot from a startup disk in your floppy drive and have it appear on the monitor?