Want to get a Powercolor R9 270X To work in my rig, please help.

KieranDavidW123

Honorable
Apr 28, 2013
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1
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Hi

I bought a Powercolor Radeon R9 270X Devil Edition from Overclockers UK a couple of months ago, I installed it, and no signal was received. My previous GPU was an NVIDIA GT 640 2GB, I uninstalled the drivers for that before I installed the 270X. Everything was plugged in right, but no signal was being received.

Here is my rig:
i3 2120 @3.3GHz
4GB DDR3 @1333MHz
H61 Motherboard
NVIDIA GT 640
Western Digital Caviar Blue 500GB 7200RPM
XFX Pro core edition 550w
Cooler Master CM-690 II Windowed.

My PC is a heavily modified Lenovo H520S, however basically every part of it has been replaced. I checked on the hardware maintenance manual and the GT 640 isn;t listed as supportable, I think that is because the H520S was originally slimline. I have no clue where to find my latest BIOS.
I would really like to get this installed as I have just been staring at the box, thinking of a solution. If nothing else is possible then I would probably just get a new CPU, motherboard and RAM.

Please, any help is appreciated.

Thanks.