Sorry for the non-specific title. I'll try and elaborate more here.
I went over the 'MY PC Won't Start' sticky, and did a search for other titles, but my problem seems to fall in-between troubleshooting steps that I see.
By that I mean, when I hit the power button on the front panel of my case, nothing on the inside of the case happens at all except I see one of the case lights come on for just a second; along with the temperature display on the front of the case.
I hear no fan, I hear no hard drive spinning, not even any semblance of a start when I hit the power button; simply quiet.
Now, my PC was working fine earlier today, but I received a new video card; eVGA GeForce 7950GT to replace a GeForce 6600. I have a ASUS P5ND2-SLI motherboard, and I believe but I'm not certain a Raidmax case, one of the ones with an openable panel door covering the drivebays and such and has a temperature display.
So after I installed the 7950 and tried to power back up, the aforementioned happened. I tried the second PCI-E port with the new card, and the same thing happened. Finally I switched back in the 6600 which has been functioning with the PC for over a year, and the same exact problem persisted.
Things I'm relatively sure of:
1. There's two really important power connectors to the motherboard? ATX12V as labeled on my motherboard manual, and the really huge one which is I guess abbreviated with a long string of letters and numbers (sorry don't know it's general name). I'm certain both of those are attached.
I'm certain the CPU-FAN power is attached.
2. The power supply voltage is set to 110, which it always has been. I can see inside of my case when the power is connected, that the motherboard LED light is green.
That's about it...I didn't build this PC, but I did replace the power supply about a month ago so had a bit of experience in doing that. I have no idea if maybe I've unintentionally disrupted power from the case to the motherboard somehow.
Any clues of what I may've done wrong is appreciated! I'm also able to take digital photos if that'll help and upload them.
I'm also willing to take it to a technician in the morning if you believe something is really wrong.