GeForce GT 640 DDR3 vs Radeon HD 6790

Intro

Compare that to the Radeon HD 6790, which has a clock speed of 840 MHz and a GDDR5 memory frequency of 1050 MHz. It also makes use of a 256-bit bus, and makes use of a 40 nm design. It is made up of 800 SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Benchmarks

These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.

3DMark Fire Strike Graphics Score

Radeon HD 6790		2150 points
GeForce GT 640 DDR3		1560 points
	Difference: 590 (38%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
Radeon HD 6790		150 Watts
	Difference: 85 Watts (131%)

Memory Bandwidth

The Radeon HD 6790, in theory, should be quite a bit faster than the GeForce GT 640 DDR3 in general. (explain)

Radeon HD 6790		134400 MB/sec
GeForce GT 640 DDR3		57024 MB/sec
	Difference: 77376 (136%)

Texel Rate

The Radeon HD 6790 should be a small bit (about 17%) better at texture filtering than the GeForce GT 640 DDR3. (explain)

Radeon HD 6790		33600 Mtexels/sec
GeForce GT 640 DDR3		28800 Mtexels/sec
	Difference: 4800 (17%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce GT 640 DDR3 is superior to the Radeon HD 6790, but only just. (explain)

GeForce GT 640 DDR3		14400 Mpixels/sec
Radeon HD 6790		13440 Mpixels/sec
	Difference: 960 (7%)

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: Bandwidth is the maximum amount of data (counted in megabytes per second) that can be transferred over the external memory interface within a second. It's calculated by multiplying the bus width by the speed of its memory. In the case of DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better 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 texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.