which one is the best?

[mohyasdgold]

my pc:
CPU is:intel pentium E5700
Mother:Gigabyte G41mT-S2P
RAM:6 GB


-MSI Radeon R7 250X 1GB GDDR5
-Gigabyte R7 250 OC 2GB GDDR3
-SAPPHIRE R7 250 1GB GDDR5 WITH BOOST
-Gigabyte GeForce GTX 550 Ti 1GB GDDR5
-Gigabyte GeForce GT 640 OC 2GB GDDR3

 

[Eduello]

I'd say the 'MSI Radeon R7 250X 1GB GDDR5' is the strongest one out of those cards.