XFX R7 250 or Sapphire 7770 vapor x?

Kyle Toralba

Honorable
Jul 20, 2013
49
0
10,530
help me decide pls, currently I'm using a r7 250 here is my computer spec
amd a8 5600k
2x4gb corsair vengeance 1600mhz
gigabyte a75m

I cant feel r7 250 on higher games like call of duty ghost still lag and semi drop rate on battlefield 3, is it better to use 7770 instead? I have it on my side now but I need new psu. so which one do you prefer and much more powerful?