Not with that power supply. And you be better off spending $240 on a single GPU than on dual GPUs. Plus that Z75 second PCI-E slot is only PCI 2.0-X4 - that may not matter on a weaker card like the 7770 but still don't think I'd go that route.
Single $240 card with that mobo is the better way.
Thanks for the reply. I posted this as a hypothetical situation because I only want to spend about $120 in a new card right now. I just thought if maybe in the future I could get another as I got the money. Now though, I don't think it'd be worth it. I'd rather just save and get something more powerful like a 7850.