GeForce GT 640 DDR3 vs Radeon HD 4730

Intro

Compare those specifications to the Radeon HD 4730, which uses a 55 nm design. AMD has set the core speed at 700 MHz. The GDDR5 RAM is set to run at a speed of 900 MHz on this card. It features 640(128x5) SPUs along with 32 Texture Address Units and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
Radeon HD 4730		140 Watts
	Difference: 75 Watts (115%)

Memory Bandwidth

Performance-wise, the Radeon HD 4730 should in theory be a little bit superior to the GeForce GT 640 DDR3 overall. (explain)

Radeon HD 4730		57600 MB/sec
GeForce GT 640 DDR3		57024 MB/sec
	Difference: 576 (1%)

Texel Rate

The GeForce GT 640 DDR3 is a lot (approximately 29%) faster with regards to texture filtering than the Radeon HD 4730. (explain)

GeForce GT 640 DDR3		28800 Mtexels/sec
Radeon HD 4730		22400 Mtexels/sec
	Difference: 6400 (29%)

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 4730, and very much so. (explain)

GeForce GT 640 DDR3		14400 Mpixels/sec
Radeon HD 4730		5600 Mpixels/sec
	Difference: 8800 (157%)

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 largest amount of data (counted in MB per second) that can be transported across the external memory interface in one second. The number is worked out by multiplying the interface width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.