GeForce GT 420 vs GeForce GTS 150

Intro

Compare those specs to the GeForce GTS 150, which comes with core clock speeds of 740 MHz on the GPU, and 500 MHz on the 1024 MB of GDDR3 RAM. It features 128 SPUs as well as 64 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce GTS 150		141 Watts
	Difference: 91 Watts (182%)

Memory Bandwidth

Theoretically, the GeForce GTS 150 should perform a bit faster than the GeForce GT 420 overall. (explain)

GeForce GTS 150		32000 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 3200 (11%)

Texel Rate

The GeForce GTS 150 is quite a bit (more or less 746%) better at AF than the GeForce GT 420. (explain)

GeForce GTS 150		47360 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 41760 (746%)

Pixel Rate

The GeForce GTS 150 is a lot (about 323%) faster with regards to full screen anti-aliasing than the GeForce GT 420, and also should be capable of handling higher screen resolutions while still performing well. (explain)

GeForce GTS 150		11840 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 9040 (323%)

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 maximum amount of information (in units of megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better 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 amount of texture map elements (texels) that can be processed per second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.