Compare any two graphics cards:

Radeon HD 3870 1GB vs Radeon R9 M275X

Intro

The Radeon HD 3870 1GB comes with a GPU clock speed of 775 MHz, and the 1024 MB of GDDR4 RAM runs at 1125 MHz through a 256-bit bus. It also is made up of 320(64x5) SPUs, 16 Texture Address Units, and 16 ROPs.

Compare those specifications to the Radeon R9 M275X, which comes with a core clock frequency of 900 MHz and a GDDR5 memory speed of 1125 MHz. It also features a 128-bit memory bus, and uses a 28 nm design. It is made up of 640 SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M275X		50 Watts
Radeon HD 3870 1GB		106 Watts
	Difference: 56 Watts (112%)

Memory Bandwidth

Both cards have the exact same memory bandwidth, so theoretically they should perform exactly the same. (explain)

Texel Rate

The Radeon R9 M275X should be much (approximately 190%) more effective at AF than the Radeon HD 3870 1GB. (explain)

Radeon R9 M275X		36000 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 23600 (190%)

Pixel Rate

The Radeon R9 M275X is a bit (approximately 16%) better at FSAA than the Radeon HD 3870 1GB, and also will be able to handle higher resolutions while still performing well. (explain)

Radeon R9 M275X		14400 Mpixels/sec
Radeon HD 3870 1GB		12400 Mpixels/sec
	Difference: 2000 (16%)

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

Display Prices

Hide Prices

Radeon HD 3870 1GB

Amazon.com

Check prices at:

Radeon R9 M275X

Amazon.com

Check prices at:

Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.

Specifications

Display Specifications

Hide Specifications

Model	Radeon HD 3870 1GB	Radeon R9 M275X
Manufacturer	AMD	AMD
Year	Nov 19, 2007	May 1 2014
Code Name	RV670 XT	Venus XTX
Memory	1024 MB	2048 MB
Core Speed	775 MHz	900 MHz
Memory Speed	2250 MHz	4500 MHz
Power (Max TDP)	106 watts	50 watts
Bandwidth	72000 MB/sec	72000 MB/sec
Texel Rate	12400 Mtexels/sec	36000 Mtexels/sec
Pixel Rate	12400 Mpixels/sec	14400 Mpixels/sec
Unified Shaders	320(64x5)	640
Texture Mapping Units	16	40
Render Output Units	16	16
Bus Type	GDDR4	GDDR5
Bus Width	256-bit	128-bit
Fab Process	55 nm	28 nm
Transistors	(Unknown) million	(Unknown) million
Bus	PCIe 2.0 x16/AGP 8x	PCIe 3.0 x16
DirectX Version	DirectX 10.1	DirectX 11.2
OpenGL Version	OpenGL 3.0	OpenGL 4.3

Memory Bandwidth: Bandwidth is the maximum amount of information (counted in megabytes per second) that can be moved past the external memory interface in a second. The number is calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, it should be multiplied by 2 once 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 anti-aliasing, High Dynamic Range 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 calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.

Display Prices

Hide Prices