GeForce GTX 650 Ti vs Radeon HD 4890 2GB

Intro

Compare all that to the Radeon HD 4890 2GB, which comes with a clock speed of 1000 MHz and a GDDR5 memory speed of 975 MHz. It also makes use of a 256-bit memory bus, and makes use of a 55 nm design. It is made up of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 650 Ti		110 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 80 Watts (73%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4890 2GB should theoretically be quite a bit better than the GeForce GTX 650 Ti in general. (explain)

Radeon HD 4890 2GB		124800 MB/sec
GeForce GTX 650 Ti		86400 MB/sec
	Difference: 38400 (44%)

Texel Rate

The GeForce GTX 650 Ti should be quite a bit (approximately 48%) faster with regards to anisotropic filtering than the Radeon HD 4890 2GB. (explain)

GeForce GTX 650 Ti		59392 Mtexels/sec
Radeon HD 4890 2GB		40000 Mtexels/sec
	Difference: 19392 (48%)

Pixel Rate

The Radeon HD 4890 2GB will be just a bit (more or less 8%) more effective at FSAA than the GeForce GTX 650 Ti, and also should be able to handle higher resolutions more effectively. (explain)

Radeon HD 4890 2GB		16000 Mpixels/sec
GeForce GTX 650 Ti		14848 Mpixels/sec
	Difference: 1152 (8%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (measured in megabytes per second) that can be transferred over the external memory interface within a second. It's calculated by multiplying the card's interface width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.