Radeon HD 4870 OC
The overclocked MSI Radeon HD 4870 runs at 780 MHz (GPU) and 4,000 MHz GDDR5 RAM clock rate—the stock clock would be 750 MHz and 3,600 MHz. The graphics chip can handle DirectX 10.1, and the sample has 512 MB. At the 1920x1200 resolution with anti-aliasing, the MSI overclock results in a 13% boost in Crysis. When you consider all of the games of the benchmark suite as a whole, 3D performance increases by 3.5% over card at stock clocks.
Its toughest opponent is Nvidia’s GeForce GTX 260. Due to the serious drop in prices, these cards are now much more competitively priced. AMD’s offering is a bit cheaper, but the GTX 260 compensates with that little extra bit of 3D speed. Still, AMD has the edge. The GTX 260, under load, is pretty loud. But it’s still much quieter than the other GT200-based card from Nvidia. AMD’s disadvantage is that power consumption in 2D mode is 147 watts for the entire system, though this is set to change with an upcoming driver.
The greatest advantage of the HD 4870 over AMD’s Radeon HD 4850 is its two-slot fan that expels hot air from the PC chassis. In 2D mode, AMD has taken acoustic output into consideration, but the slow fan speed means that the GPU temperatures hovers around 76 degrees C and more heat is transferred to other PC components. In order to avoid these high figures, check out the Gainward Expertool v4.0 for the 4870, which enables manual fan control.
The fan on our MSI sample gets alternates between loud and soft in 2D mode. The stock configuration, not overclocked, does not use this fan profile. Either the RPMs either remain constant on that board, or the change is too quiet to be heard. Under 3D load, the power supply for the test system using the Radeon HD 4870 draws up to 288 watts. A branded power supply with 240 to 280 watts and 20 to 23 A on the 12 volt rail should be sufficient for a standard system.
