what is the difference between these two psu's

Solution
The B2 series units are made by Super Flower and are excellent quality. The B1 series units are made by FSP, they are much lower quality. Do not use the B1 series units with gaming cards or overclocked rigs. Get the B2, G2, P2 or V series units if you go with EVGA.
The B2 series units are made by Super Flower and are excellent quality. The B1 series units are made by FSP, they are much lower quality. Do not use the B1 series units with gaming cards or overclocked rigs. Get the B2, G2, P2 or V series units if you go with EVGA.
 
Solution