Sapphire r9 270x low fps (not getting the performance shown online)

2 months ago i build my new pc with my center piece the r9 270x. But during these couple of months i tried and tried to get the performance out of my card I was promised.

I tried everything: Different drivers, looking in the bios for options etc... But nothing works and i am realy mad about this!

 

So if anyone could help me with my problem i would be very thankful.

 

system specs: 

 

CPU: AMD FX - 6300 6 [email protected] 3.5Ghz

GPU: Sapphire AMD R9270X dual-x

RAM: 8 GB Corsair Valueselect 1333 Mhz, running in dual channel

MOBO: ASUS M5A97 LE R2.0

CASE: Cooler master N300

HDD: WD 1TB 7200 rpm SATA 3 green

PSU: Corsair CX600 600 watts

OS: Windows 7 Ultimate x64

How much is the difference?

i get 40 fps on battlefield 4 on all settings so that is a bit strange i dont know why. Also on minecraft i get 60 fps. My old gtx 650 had 120+ fps on minecraft.

Vsync on or off?