New motherboard, no video output

Are you running a dedicated video card? If you are, try without it just using the onboard video.

If you get video, make sure the bios is set to first init or default video(called different things on different boards) PCI-E

Failing that(lets say you have just the onboard video)

Remove all but 1 stick of memory and try again(if this works, you may need to adjust memory settings or may even have 1 bad stick of memory, this happens from time to time). The goal of trouble shooting is to just remove everything not needed to test.

Does the PC beep at all? Does it have a speaker so it can beep?

The list can go on for ever....

Please see here. I know you have done some of this, but there is a good list of things to check here

http://www.tomshardware.com/forum/261145-31-perform-ste...

Just curious, but would it have anything to due with the fact that I don't have a screw in each slot on the motherboard holding it in place? It's firm and doesn't move an inch. Another thing, mine doesn't have standoffs for the screws. Could that be an issue as well...?

No, a board will run sitting on a table(I have also had boards what the case was missing the holes for the far end, it never caused any issues). I test most boards this way to make sure they work before i bother installing.

That said, It may be worth removing the board. It does not have to have the memory or cpu and heatsink removed. Then place it on a table on that plastic bag it came in(or even some paper will work, you just do not want it on anything that conducts electricity). Connect up just your keyboard monitor(the the built in card) and power supply(24 pin and CPU power 4 pin connector). Leave out hard drives and all that other stuff.

Give it a try like that. Please note you will have to connect the power switch from the case or short the 2 pins for the power button(generally done with a screw driver, but be very careful). do NOT short the wrong pins or you can break the board. If you have any doubts, use the power switch from the case.

The goal here is to make sure NOTHING can touch the board so it is isolated from everything else.

Two days of worrying and it all stems from the fact that the prongs on my processor were bent, and it wasn't inserted all the way. Thanks a bunch for the help, looked over most of the things you suggested, helped quite a bit to deduce what was wrong.  

Your lucky you caught that(one of those things that just does not seems to happen often on socket systems).

So everything is booting up?

Make sure you used new thermal paste when you reinstalled the heatsink.

Im having a similar issue with a new Asus P5ld2 board. The difference is this board doesnt have onboard video so I have to leave the video card on when Im testing. It fires up, fans spinning at full speed. When I had the hard drive connected you can hear the hard drive going. No beeping from the board and Ive tried with different ram. Any ideas? Its driving me crazy!