At the core of this card is the new, swanky, R770-class chip which is built using a 55nm process – this smaller die allows AMD to be ultra-aggressive in its pricing because there are not as many die’s being discarded (the smaller the die, the better the final yields are). NVIDIA is just now churning out 55nm parts with an “emergency” card called the GeForce 9800GTX+ - we’re not sure what the plus really means, but can tell you that it was pulled out at the last second in order to compete with the Radeon HD 4850.

AMD’s 4870 is the same GPU as the 4850 with the following changes – 750MHz core, 900MHz memory clock (3600MHz data rate) and comes with a dual-slot setup which gets the heat out of the PC (which I’m a huge fan of). It has the same 256-bit memory interface, 965 Million transistors, 40 texture units, 800 stream processors and a partridge in a pear tree. The easiest way to think of the 4870 is that it’s a clocked-up 4850 with GDDR5 –AMD needed this newer memory technology to provide enough bandwidth for the GPU.

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