Radeon HD 4650 1GB vs Radeon HD 6950

Intro

Compare all that to the Radeon HD 6950, which features core clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 memory. It features 1408 SPUs along with 88 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4650 1GB		55 Watts
Radeon HD 6950		200 Watts
	Difference: 145 Watts (264%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6950 should be much faster than the Radeon HD 4650 1GB in general. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 4650 1GB		22400 MB/sec
	Difference: 137600 (614%)

Texel Rate

The Radeon HD 6950 should be much (approximately 267%) faster with regards to anisotropic filtering than the Radeon HD 4650 1GB. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 4650 1GB		19200 Mtexels/sec
	Difference: 51200 (267%)

Pixel Rate

The Radeon HD 6950 will be quite a bit (about 433%) faster with regards to FSAA than the Radeon HD 4650 1GB, and should be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 4650 1GB		4800 Mpixels/sec
	Difference: 20800 (433%)

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 maximum amount of information (in units of MB per second) that can be moved past the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.