The 7770's a great card for Minecraft. It's what I chose for my build since I, like you, only really play Minecraft at the moment. The 7770 normally can get me 60+ FPS on the highest settings, so I'd definitely recommend it to anyone who's just looking to play Minecraft with it.

yea. but if ur max is 150 hit up the ati radeon 7770 or the nvidia gtx 650 depending on if u like ati or nvidia, but personally i would spend the extra money and get a 660ti, it will last longer in terms of gaming, games keep getting better - BUT if all u do is minecraft then the $150 lock is good. But dont forget tastes change and as u get older u might play other games so thats why i would pick a 600ti.

But idk ur specs so u may not get full potential out of the 660ti if u have an older processor and motherboard, which i think u do since u only have PCIe 2.0

Either way, go with 7770 or 650 if u only play minecraft, otherwise boost it up to the 660ti which is best value for dollar and 7th in the lead of high end cards.

Radeon HD 7770. Its also compatible for PCI-e 3.0 - but no card fully utilizes even the 2.0 yet so you will be perfectly fine.