Not sure if GPU will fit in case

Solution
If that is the case you definitely want to go for, then you'll need to find a low profile, single slot video card, as it doesn't have provision for a full height expansion card.
Off the top of my head, the most powerful modern card which meet this criteria is the low profile versions of the HD7750.

Alternatively, you could look at swapping to a taller case, or one with two full height expansion slots, if you want to fit that graphics card (I assume you already have it). A Coolermaster Elite 120/130 is quite a lot bigger but fits standard sized parts and is still compact enough to be moved around. It's also pretty cheap. If you want something fairly hassle free, they'd be worth a look.

Rammy

Honorable
If that is the case you definitely want to go for, then you'll need to find a low profile, single slot video card, as it doesn't have provision for a full height expansion card.
Off the top of my head, the most powerful modern card which meet this criteria is the low profile versions of the HD7750.

Alternatively, you could look at swapping to a taller case, or one with two full height expansion slots, if you want to fit that graphics card (I assume you already have it). A Coolermaster Elite 120/130 is quite a lot bigger but fits standard sized parts and is still compact enough to be moved around. It's also pretty cheap. If you want something fairly hassle free, they'd be worth a look.
 
Solution