GeForce GT 640 DDR3 vs Radeon HD 4670 1GB

Intro

Compare those specifications to the Radeon HD 4670 1GB, which has a core clock speed of 750 MHz and a GDDR4/GDDR3/DDR3/DDR2 memory speed of 1100 MHz. It also features a 128-bit memory bus, and uses a 55 nm design. It features 320(64x5) SPUs, 32 Texture Address Units, and 8 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
Radeon HD 4670 1GB		70 Watts
	Difference: 5 Watts (8%)

Memory Bandwidth

Theoretically, the GeForce GT 640 DDR3 should be quite a bit faster than the Radeon HD 4670 1GB overall. (explain)

GeForce GT 640 DDR3		57024 MB/sec
Radeon HD 4670 1GB		35200 MB/sec
	Difference: 21824 (62%)

Texel Rate

The GeForce GT 640 DDR3 should be a little bit (more or less 20%) faster with regards to AF than the Radeon HD 4670 1GB. (explain)

GeForce GT 640 DDR3		28800 Mtexels/sec
Radeon HD 4670 1GB		24000 Mtexels/sec
	Difference: 4800 (20%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the GeForce GT 640 DDR3 is superior to the Radeon HD 4670 1GB, by far. (explain)

GeForce GT 640 DDR3		14400 Mpixels/sec
Radeon HD 4670 1GB		6000 Mpixels/sec
	Difference: 8400 (140%)

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 largest amount of information (counted in MB per second) that can be moved across the external memory interface within a second. It is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, 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 can be applied per second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the graphics 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 maximum amount of pixels that the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.