Recently AMD introduced their latest graphics card, the Radeon HD 4870. It is based on the same RV770 GPU that is present on the Radeon HD 4850, too. The major difference is that the Radeon HD 4870 uses the new GDDR5 memory versus only GDDR3 memory. Certainly the biggest benefit of GDDR5 is that is offers twice the memory bandwidth than GDDR3 at the same clock. As a result the Radeon HD 4870 has almost double the memory bandwidth available, even though its memory clock is slightly lower than the Radeon HD 4850. Another difference is that the Radeon HD 4870 uses a dual slot cooling solution allowing AMD to increase the core clock by 125MHz to 750MHz. - techPowerUp

Diamond Radeon HD 4870 512MB Video Card Review

Diamond's Radeon HD 4870 is fully based on the AMD reference design, but Diamond has already announced a special Black Edition card that allows much higher clock speeds. Diamond uses a sleek black package with Ruby printed on both sides. The back side goes into some more detail about the product. The Diamond Radeon HD 4870 looks exactly the same as the AMD reference design card, except for the sticker on the fan hub. Like the Radeon HD 3870, the Radeon HD 4870 uses a dual slot cooler design. The graphics card has two DVI ports, basically the most common output configuration these days.

The cooler consists of a copper baseplate that makes direct contact with the GPU and an aluminum array of cooling fins. Both are connected by a heatpipe to ensure optimum heat transfer. Compared to the Radeon HD 4850 the cooler is heavier and more complex. In addition to cooling the GPU, the cooler also cools the eight memory chips and the voltage regulator circuitry. You can use two, three or four of these Radeon HD 4870 cards in CrossFire to build an even more powerful rig. The power to the card is supplied via two 6-pin PCI Express connectors, and will not work without both power connectors connected to it.

Yum, nice GDDR5 memory chips. They are made by Qimonda bearing the 40X markings. The 40X stands for the data rate of 4.0Gbps per pin. Effectively this means that chips are rated at 2000MHz real clock. Please note that GDDR5 offers twice the bandwidth per pin at the same clock. So a 256-bit GDDR5 card has the same bandwidth as a 512-bit GDDR3 card at the same clock. This is a key factor in keeping design costs down. As you know NVIDIA uses a 512-bit memory bus on the GeForce GTX 280 which dramatically increases total cost. ATI gets the same bandwidth with a 256-bit GDDR5 bus at a fraction of the price.

If you are in the market for a new graphics card in the $300 range, the Radeon HD 4870 should be your weapon of choice. However, if you can settle with lower performance, you may as well get the Radeon HD 4850 which runs quieter and offers more performance for your hard earned cash. Even though you have to pay a premium for the extra performance, the AMD Radeon HD 4870 has the potential to revolutionize the $300 segment. It offers tons of performance to ensure all the latest games run silk smooth. If you plan on gaming on your big screen, the card is a good choice too as it supports a digital HDMI connection.

AMD has successfully introduced GDDR5 memory to the graphics market, which is a new generation of memory chips that is used on the Radeon HD 4870 for the first time. Compared to previous generations of graphics memory this new architecture offers twice the bandwidth at the same clock and bus width. Several new power saving features were also added to the RV770 chipset, but in our opinion these are not optimally configured at the moment resulting in higher power draw and more fan noise when the card is idle. Also, the low fan speed lets the GPU get quite hot.