Three Radeon HD 4870s: 512MB, 1GB, And 2GB
Powercolor AX4870 512MD5-G Radeon HD 4870 512MB
We'll begin with the 512MB card, a PowerColor Radeon HD 4870.
This card is overclocked from the factory with a GPU speed of 770 MHz compared to the reference 750 MHz, so we'll lower this to the reference speed for our testing to keep everything on an even keel. The GDDR5 memory runs at 900 MHz, which is the same as the standard Radeon HD 4870 reference speed. This card retails for about $135 on Newegg.
XFX 487A-ZHFC Radeon HD 4870 1GB
This XFX version of the Radeon HD 4870 comes with 1,024MB (1GB) of RAM, and runs at the reference 750 MHz core and 900 MHz GDDR5 memory speeds. This model costs about $145 on Newegg.
Sapphire Vapor-X Radeon HD 4870 2GB
This Sapphire card is equipped with four times the memory of the 512MB card. While it sports the same 750 MHz core and 900 MHz GDDR5 memory speeds as the reference Radeon HD 4870, it comes with a unique aftermarket cooler. This model costs about $227 on Newegg.
Now that you've seen the contenders, let's have a closer look at the test system and move on to the benchmarks.