PSU Smoking and Graphics card not working

Yesterday my 500w powersupply started smoking up so I went out and bought a Thermaltake Lightpower 700w powersupply. After I finished rewiring my computer I noticed my graphics card wasn't working on my computer so I changed my input from HDMI to VGA to use the integrated graphics card.

I'm not sure what caused the original 500w powersupply to smoke up and why my graphics card doesn't work anymore. I'm unsure whether the graphics card isn't working because i've made a mistake in wiring the connection from my PSU to motherboard or if the PSU killed it.

Yesterday I also received a USB Wireless Receiver for Xbox which I plugged in the top USB slots I never use, could this be a reason for the PSU faulting? Sometimes when I plug in a USB device the metal surrounding the slots spark up a little which is why I mentioned the USB wireless receiver.

Below are the specifications of my system:

AMD Phenom X4 955 Black Edition 3.2ghz
Gigabyte GA-880GM-UD2H
Kingston 2x4GB Ram 1333mhz
(New PSU) Thermaltake Lightpower 700w - (Old PSU) 500w
Sapphire Radeon HD6850 1GB GDDR5 Firmware flashed to HD6870

------------------------------------------------------------------------------------------------------------------------------------------------------

Thanks for your help in advance.

It is entirely possible that when the PSU died it took the video card with it. Have another computer you can test the card in?

Thanks for the reply. I don't have another computer to test it out on. ATM I gave the GFX card to the shop I bought it from and they are going to try repair it under warrantee but if they manage to fix it, they'll notice it's flashed and probably cancel my warrantee. If the PSU did damage my GFX card, do you think it would be repairable? Cheers.