SAPPHIRE HD Radeon 7870 not performing as well as it used to

Danoded

Honorable
Dec 4, 2013
420
0
10,960
The performance of my graphics card seemed to deteriorate overnight as all my games now run terribly. My games used to run perfectly smooth at a very good playable FPS, but now they all play with lots of hiccups and FPS has dropped dramatically. I've also realised that the GPU usage has dropped. Before, it used to be in the 80-90s, but now it averages at between 50-70 in every game with a barely playable FPS (25-30). Even games that ran perfectly smooth are now stuttering, jittery and some are borderline unplayable. My CPU usage is low as well, avereraging at about 65-70 at shown here when I'm playing AC:IV

http://imagizer.imageshack.us/a/img811/4633/tu1n.jpg

Heat is definitely not an issue here, I have the latest 14.3 drivers installed, my PSU is more than enough so I am really stuck on what could be causing the GPU never to hit 99 or even 80 in most cases. It can't be a CPU bottleneck because I have been able to run these games smoothly in the past without any hiccups and I see people with similar setups getting a good fps constantly so please don't bring that up.

My other system specs are:

CPU-FX 4130 3.8GHz (Zambezi)
MOBO-Biostar A960D+
PSU- Corsair CX600M
RAM-8gb DDR3 1333Mhz
 

Danoded

Honorable
Dec 4, 2013
420
0
10,960