Help! MSI-P6N-SLI-Platinum NO POST. Reply Quick!

[Slooch]

Ok guys, dunno if you have heard of the new P4 motherboards that come with a 8 pin 12v. Power connectors.

Well any way I got everything pluged in correctly, I have built many machines myself and this new one wont post.

****This is what I think the problem is though. Every componant on this computer is brand new out of the box. I installed everything corectly and tried to post the computer. It wouldnt post. So I begain to test things and the first thing I tested was the powersupply.
****Now I want to note this powersupply is not like most the key difference is its a 24 pin power connector and it has 2 yes two 4 pin power connectors each at 12volts.

So I tested this powersupply on a standard Power tester that plugs in to a 20 pin and the tester gave me a red danger light and 2 green lights that normaly light up one was flickering and one was off completely.

So my question would be.... is this power tester that i used did it give me a reliable signal that the powersupply was bad? do I need to get a new power tester that accepts 24pin?

I need to know because im sending for a new powersupply and dont want to recieve it if this one I have works.

So please reply quickly.

Specs

MSI P6N SLI Platinum
Intel Core 2 Duo E6400* 2.13 Ghz
2 GB DDR 2 Ram Dual channel operation (yes installed corectly) (only have one installed any way to test motherboard post.)
Faitality Silent but deadly GFX card. (Geforce 7600GT)
Old *** modem installed.