Help! My graphics card won't work!

[combustable_mcnugget]

I setup my gaming rig about a year ago with a friend of mine. It has been working perfectly fine since. Until about a month ago, I got serious lag and noticed my graphics card fan wasn't working. There was no way the fan would ever work again. I ordered the Accelero Mono Plus by Arctic to replace the old heat sink on my graphics card. I just attached it on and everything seemed to work fine. During the process of installing the cooler I had to remove the plastic casing over the heatstroke and fan. It isn't meant to go back on. But now my Computer is screwy.
When my computer is booting it will display for a few seconds then the monitor loses connection. It doesn't matter if it is by VGA, DVI, or HDMI, it just won't work. I looked around inside the computer and it isn't physically interfering with anything, and nothing got unplugged. Also when I take out the graphics card, and go back to integrated graphics, everything works fine. I have been wondering will I need a new graphics card?

Here are my Specs:
CPU: Intel i5 2500k
Graphics card: XFX Radeon HD 6870 1GB DDR5 Single Fan
Motherboard: AsRock Z68 Extreme3 Gen3
RAM: Corsair Vengence 8GB (2x4GB)

Please respond soon!

 

[Ironsounds]

Hello... did ya apply thermal paste to the GPU/Heatsink?

also try a alcohol/swab and clean your graphic card connector pins/terminals... and re-seat video card.

 

[combustable_mcnugget]

Yes I did already apply thermal paste to the GPU and heatsink. I tried cleaning the connectors/pins and I re-seated the video card and nothing has changed. Thanks anyways, but do you have any other ideas?

 

[Ironsounds]

Hello... if all your power connections to the Card are good... fan connected to the Video card, and turns... the only other things I can think of that I would do would be...

1) try the card in a friends computer... determine if you have a PCIX slot problem.

2) re-flash the BIOs... determine if you had a static problem when installing the Heatsink and fan.