GeForce GT 640 DDR3 vs GeForce GTX 570

Intro

Compare those specs to the GeForce GTX 570, which features a clock speed of 732 MHz and a GDDR5 memory speed of 950 MHz. It also makes use of a 320-bit memory bus, and makes use of a 40 nm design. It features 480 SPUs, 60 TAUs, and 40 ROPs.

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

GeForce GTX 570		4387 points
GeForce GT 640 DDR3		1560 points
	Difference: 2827 (181%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
GeForce GTX 570		219 Watts
	Difference: 154 Watts (237%)

Memory Bandwidth

In theory, the GeForce GTX 570 will be 167% quicker than the GeForce GT 640 DDR3 overall, due to its higher bandwidth. (explain)

GeForce GTX 570		152000 MB/sec
GeForce GT 640 DDR3		57024 MB/sec
	Difference: 94976 (167%)

Texel Rate

The GeForce GTX 570 should be much (more or less 53%) better at texture filtering than the GeForce GT 640 DDR3. (explain)

GeForce GTX 570		43920 Mtexels/sec
GeForce GT 640 DDR3		28800 Mtexels/sec
	Difference: 15120 (53%)

Pixel Rate

The GeForce GTX 570 should be a lot (about 103%) better at anti-aliasing than the GeForce GT 640 DDR3, and able to handle higher screen resolutions without slowing down too much. (explain)

GeForce GTX 570		29280 Mpixels/sec
GeForce GT 640 DDR3		14400 Mpixels/sec
	Difference: 14880 (103%)

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 (measured in MB per second) that can be transferred over the external memory interface in one second. It's worked out by multiplying the bus width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the 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 amount of pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on 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 potential to reach the max fill rate.