Graphics Cards running at bare minimum

I am currently having problems with my computers graphics card. I have a GIGABYTE 7870 OC and for some reason it is only running at the bare minimum of its potential. The GPU clock is only running at 300 MHz and the Memory clock is only running at 150 MHz. I've had the graphics card for about a month and everything was running fine on it, it was preforming were I wanted it to preform, but I recently rewired my computer so I could get better air flow in it and now I have this problem. I thought I might have broken the card when I was rewiring it so I tried putting in my older graphics card, an ASUS 5750FORMULA and it had the same problem it was only running at its bare minimum. I have no idea what this problem could be stemming from but its very frustrating when I was running LoL at 180FPS and now I am having a hard time getting 40FPS. Any help would be great.