GeForce GTX 960 vs Radeon HD 4890 1GB

Intro

Compare all of that to the Radeon HD 4890 1GB, which comes with a clock speed of 1000 MHz and a GDDR5 memory frequency of 975 MHz. It also uses a 256-bit bus, and makes use of a 55 nm design. It is made up of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 960		120 Watts
Radeon HD 4890 1GB		190 Watts
	Difference: 70 Watts (58%)

Memory Bandwidth

In theory, the Radeon HD 4890 1GB should be 11% faster than the GeForce GTX 960 in general, because of its higher bandwidth. (explain)

Radeon HD 4890 1GB		124800 MB/sec
GeForce GTX 960		112000 MB/sec
	Difference: 12800 (11%)

Texel Rate

The GeForce GTX 960 should be a lot (approximately 80%) more effective at AF than the Radeon HD 4890 1GB. (explain)

GeForce GTX 960		72128 Mtexels/sec
Radeon HD 4890 1GB		40000 Mtexels/sec
	Difference: 32128 (80%)

Pixel Rate

If using high levels of AA is important to you, then the GeForce GTX 960 is the winner, by far. (explain)

GeForce GTX 960		36064 Mpixels/sec
Radeon HD 4890 1GB		16000 Mpixels/sec
	Difference: 20064 (125%)

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 max amount of information (in units of megabytes per second) that can be moved across the external memory interface in one second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.