Powercolor hd 6950 not working on dh61ww

[Haider Abbas]

Hi all,
I have a Intel Core I5-2400 + Intel DH61WW.

I bought a PowerColor AMD/ATI Radeon HD6950 2 GB GDDR5 Graphics Card and also a 500w PSU.

But still my computer isn't working kindly advise.

 

[Haider Abbas]

Yes I had connected the two six pin power supply to graphic card
I have circle 500 watt..