Graphics card isn't being detected

Hello,
I have recently purchased a new computer and when installing the graphics card - nothing shows up on the screen.

When I use the onboard graphics, everything is fine, yet when I put in the graphics card, nothing shows up on the screen.

Is there anyway to fix this? I have read a few articles online, who say about using driversweeper to remove all the drivers and reinstalling them but this doesn't work.

I know that power is getting to the PCI-E slot, as the fan is spinning on the card, and in the BIOS settings, the primary graphics adapter is set to PCI-E.

Please help!

Specs:
CPU: Intel Q8400
Motherboard: MSI G41M-P25
RAM: Corsair XMS3 4GB
Graphics Card: Sapphire HD6870
OS: Windows 7 Home Premium 64bit


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Liam.

Did you plug in the power to the card? It takes more than the power from the slot.....

This may sound simplistic but turn off your computer...unplug the power supply plug...touch the power supply to get rid of any static electricity...take out the GPU and put it back in. This worked for me when Windows was only showing 1 GTX 460.

Give it a shot. It won't hurt to try it.