GeForce GT 640 DDR3 vs GeForce GTX 980 Ti

Intro

Compare all of that to the GeForce GTX 980 Ti, which features GPU clock speed of 1000 MHz, and 6144 MB of GDDR5 memory set to run at 1750 MHz through a 384-bit bus. It also is comprised of 2816 Stream Processors, 176 Texture Address Units, and 96 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 980 Ti		17120 points
GeForce GT 640 DDR3		1560 points
	Difference: 15560 (997%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
GeForce GTX 980 Ti		250 Watts
	Difference: 185 Watts (285%)

Memory Bandwidth

The GeForce GTX 980 Ti, in theory, should be much faster than the GeForce GT 640 DDR3 overall. (explain)

GeForce GTX 980 Ti		336000 MB/sec
GeForce GT 640 DDR3		57024 MB/sec
	Difference: 278976 (489%)

Texel Rate

The GeForce GTX 980 Ti should be much (more or less 511%) faster with regards to anisotropic filtering than the GeForce GT 640 DDR3. (explain)

GeForce GTX 980 Ti		176000 Mtexels/sec
GeForce GT 640 DDR3		28800 Mtexels/sec
	Difference: 147200 (511%)

Pixel Rate

If using a high resolution is important to you, then the GeForce GTX 980 Ti is a better choice, by far. (explain)

GeForce GTX 980 Ti		96000 Mpixels/sec
GeForce GT 640 DDR3		14400 Mpixels/sec
	Difference: 81600 (567%)

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 (counted in MB per second) that can be transported over the external memory interface within a second. It is worked out by multiplying the bus width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This figure is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the graphics 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 amount of pixels that the graphics chip can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.