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/