GeForce GT 340 vs GeForce GT 420

Intro

Compare all that to the GeForce GT 420, which comes with GPU core speed of 700 MHz, and 2048 MB of GDDR3 RAM set to run at 900 MHz through a 128-bit bus. It also is comprised of 48 SPUs, 8 TAUs, and 4 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce GT 340		69 Watts
	Difference: 19 Watts (38%)

Memory Bandwidth

Theoretically speaking, the GeForce GT 340 will be 89% faster than the GeForce GT 420 in general, because of its higher data rate. (explain)

GeForce GT 340		54400 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 25600 (89%)

Texel Rate

The GeForce GT 340 is quite a bit (more or less 214%) better at texture filtering than the GeForce GT 420. (explain)

GeForce GT 340		17600 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 12000 (214%)

Pixel Rate

The GeForce GT 340 is a lot (approximately 57%) more effective at anti-aliasing than the GeForce GT 420, and able to handle higher screen resolutions better. (explain)

GeForce GT 340		4400 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 1600 (57%)

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 information (measured in megabytes per second) that can be moved over the external memory interface in one second. The number is calculated by multiplying the bus width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly write to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the card's clock speed. 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 rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.