Computer crashes every time i try to start a game after installing new graphics

[chrislax]

Hello,
last week i purchasd a sapphire radeon hd 4870 x2 2gb gddr5. i had to buy a bigger case and bought a 750w power supply to install it because of its size and power connectors.I am running windows 7 ultimate 64bit with a core 2 duo 2.5ghz,8gb ram on a asus p5g41c-m lx motherboard. i was running a palit geforce gt 240 before with no problems but now iv got the new card in it crashes every time i try start up any game. ive updated my bios,installed the latest graphics drivers and software and rienstalled them.ive updated windows,my chipset drivers,audio drivers the works. please can someone help ?

 

[Sunius]

How many power connectors did you connect to the card from the power supply unit?

 

[dxristos]

try to reseat the GPU. I had the same problem after installing a new GPU, every game was crashing. Removed the GPU and installed it back and everything seems to work fine now.