Gigabyte NVIDIA GeForce GTX 650 2 GB GDDR5 GV-N650OC-2GI Graphics Card VS Sapphire AMD/ATI HD 7770 OC Edition 1 GB GDDR5

I don't know how the two cards do in Bioshock Infinite but in Crysis 3 the 7770 is a bit faster and overall the 7770 is a bit more powerful of a card than the 650 even with the difference in memory. 2GB in my opinion is kind of useless on a card that's GPU isn't powerful enough to use the high AA and resolution settings that are needed actually use that much memory keep the FPS at a playable level.
 

So Sapphire AMD/ATI HD 7770 OC Edition 1 GB GDDR5 is a good choice than Asus NVIDIA GeForce GTX 550 Ti 1 GB GDDR5 Graphics Card/ Gigabyte NVIDIA GeForce GTX 650 2 GB GDDR5 GV-N650OC-2GI Graphics Card
 


The 7770 is also faster than a 550 Ti.

So to sum it up of all the cards you've listed so far the 7770 is still the best.
 
GeForce GTX 650 vs Radeon HD 7770

Intro

The GeForce GTX 650 has a GPU clock speed of 1058 MHz, and the 2048 MB of GDDR5 memory runs at 1250 MHz through a 128-bit bus. It also features 384 SPUs, 32 TAUs, and 16 ROPs.
Compare all that to the Radeon HD 7770, which features a core clock frequency of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also makes use of a 128-bit memory bus, and uses a 28 nm design. It features 640 SPUs, 40 TAUs, and 16 Raster Operation Units.

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)


GeForce GTX 650 64 Watts
Radeon HD 7770 80 Watts
Difference: 16 Watts (25%)

Memory Bandwidth

The GeForce GTX 650, in theory, should perform a bit faster than the Radeon HD 7770 in general. (explain)

GeForce GTX 650 80000 MB/sec
Radeon HD 7770 72000 MB/sec
Difference: 8000 (11%)

Texel Rate

The Radeon HD 7770 is just a bit (approximately 18%) faster with regards to AF than the GeForce GTX 650. (explain)
Radeon HD 7770 40000 Mtexels/sec
GeForce GTX 650 33856 Mtexels/sec
Difference: 6144 (18%)

Pixel Rate

The GeForce GTX 650 is a little bit (approximately 6%) better at full screen anti-aliasing than the Radeon HD 7770, and also capable of handling higher resolutions without slowing down too much. (explain)
GeForce GTX 650 16928 Mpixels/sec
Radeon HD 7770 16000 Mpixels/sec
Difference: 928 (6%)

source


http://www.hwcompare.com/13467/geforce-gtx-650-vs-radeon-hd-7770/