7750 vs 625

So my friend got a prebuilt PC, which I told him not to etc etc.

He used it for gaming, and the specs are an i7-4770(not k) and a GTX 625, kinda unbalanced much?

So he was considering buying my old 7750 2GB ddr3 model to replace his card. I will give it to him for a good price, he just wants to know if its an upgrade.

I usually know about this, but the 625 is hard to pin down.
 
Yeah I know its really bad to buy a PC pre built, but he lacked the knowledge and his parents lacked the confidence in him to learn.

I know the DDR3 model is weaker, but it still should be better than the 625 (which could be a 620, because I dont trust his ability to figure out which one it is)