A monitor not coming on doesn't mean the vid card necessarily simply because thats where the signal comes from...if you don't hear your computer BEEP once signalling that it's atleast POST'ing then you have hardware problem in which it could be the mobo, CPU, vid card, or RAM.
Take out the vid card and see if the motherboard beeps...if it doesn't, it's not the vid card.
Repeat same with RAM...see if it beeps when you take out the RAM...if it doesn't, you may need to remove the whole motherboard and put it on the mobo box with an antistatic bag ontop of the box to see if the mobo was shorting out..
Try reseting the CMOS as the most basic of troubleshooting attemps