I had a XFX Radeon HD 5670 Card it worked properly for 3 years suddenly last week the display stopped working....... but if i remove the gfx card and connect it to on board graphics it works fine, so i bought a new gfx card ZOTAC NVDIA 630 , The same problem occurs there is no display, but the fans of both the gfx card spins. There is a chance that 1/20 power off and power on that the graphics card works , if the graphics card is working i cannot restart my comp as the display goes off again, Could you guys please help me about the problem?