Unusual GPU Numbers, why?

[PCGamesBeLike]

On my 750 Ti, I've overclocked it to 1364MHZ on the GPU Core Clock, and 1455MHZ on the GPU Memory Clock, but I'm still getting really odd numbers.

 

On 720p at High (no AA) settings in the Unigine Valley test, it got a score of 2233. I don't know if that's bad or not, but it seems slightly low for 720p.

 

But the really confusing part is the GPU numbers in GPU-Z. The card never used more than 679MB's for such an intensive test despite being at 720p, but it has 2GB's. The power consumption was fine at about 112.4 TDP at max.

 

EDIT: GPU load only shows at 0% throughout the whole thing because I had K-Boost on, so I need to post a new picture.

 

The GPU-Z in the attached pictures is from directly after the Unigine Valley test.

 

Could the motherboard be at fault? Because up to this point I've tried absolutely everything besides replacing the RAM or MoBo. It's working better than it was, but only because of the overclock.

 

Specs:

i5-2320

Generic Acer MoBo (which could be an issue, since it's running at PCI-E 2.0, but it shouldn't be major)

8GB DDR3-1333 (could be faulty RAM or the RAM clock speed)

GTX 750 Ti EVGA Single Fan 2GB

1TB HDD

500W Cooler Master