Direct x 11.2 not installed?

I have a gigabyte r9 270x oc gpu and have windows 8.1. I am very frustrated with these as I upgraded to windows 8 for the performance boost. And I don't have one lol. Is there any reason why this could be happening?


Performance boost in what?

Battlefield 4

In what way does it not improve? 

On windows 7 I had about 30-60 fps. mostly avg 34 fps. My specs are 

Radeon R9 270x Gigabyte OC.

PSU: 600b evga 600 watt bronze certified.

CPU: AMD Athlon X4 750k

RAM: 4gb of corsair vengence ram.

Motherboard: MSI FM2-A75MA-E35 FM2 AMD A75

COOLING: stock 

STORAGE: 500gb hard disk, 250gb hard disk, 200gb hard disk all 7200

People said on forums that windows 8.1 will improve fps and direct x 11.2 will also. for some reason I only have direct x 11.