Black Screen after installing RAM

[LordRendar]

So I installed a DDR 3 4gb stick into my N68C-5UCC ASROCK mobo. i tried to boot the pc but there was no starting beep.turns out that the mobo only accepts ddr3 ram if I use a AM3 Processor.
So I put my 2 1GB DDR2 sticks back (its an upgrade mobo,where I got both DDR3 and DDR 2 slots)
and I hear the PC boot,do the starting beep and hear the Windows starting theme,but my monitor is black. I tried re-plugging the Monitor Cable into the Graphic-Card to no avail. Any help?

 

[strawman]

All the fiddling around in your PC probably loosened something. Remove and then reinstall the video card, memory, and the various cables on the mobo and try it again.

 

[PatrThom]

Swapping memory may have also reset the BIOS to prefer integrated graphics, if present.

--Patrick

 

[sixpackshaker]

were you using anti-static protection?

 

[Chibibar]

how many DDR3? I am required to fill in all THREE slots for it to work.

 

[LordRendar]

Thanks stienman.I did what you recommended,plus i took out the graphic card,removed the dust that settlet on the mobo and after plugging everything back in,it workel like a charm again.

 

[Chibibar]

Thanks stienman.I did what you recommended,plus i took out the graphic card,removed the dust that settlet on the mobo and after plugging everything back in,it workel like a charm again.

Those pesky dust. I always use aircan on my mobo when I am changing stuff. I didn't even think of that