AMD Radeon HD 6850 & HD 6870 Launch Review - PAGE 16

Temperature:

To measure core GPU temperature, MSI's Kombustor was used. The idle temperature was taken after leaving nothing running for up to 15 minutes. The load temperature was taken 15 minutes after starting Kombuster for Multi-Core graphics cards.

The temperatures of the new 6800 series core were higher than expected, but not surprising as the cores are still 40nm. The HD 6850 had the lowest temperature out of all the new cards, but even it nearly reached the 80°C mark when under full load.

The Diamond HD 6870 XOC ran a little hotter than the reference card, but this is to be expected with the additional clock speed.

Power Usage:

To measure power usage, a Kill A Watt P4400 power meter was used. Note that the above numbers represent the power drain for the entire benchmarking system, not just the video cards themselves. For the 'idle' readings we measured the power drain from the desktop, with no applications running; for the 'load' situation, we took the sustained peak power drain readings at the end of a 30 minute Kombustor run.

Unlike the temperatures, the power usage is much improved over the Cypress cores. Even after overclocking the HD 6870 to 970/1140MHz, it still consumed less power than a reference HD 5830, and in CrossFire the 6800 series cards still used less power than a single Nvidia GTX 470.

The Diamond XOC does have a slight power usage increase due to the factory overclock, but at load it only accounts for a 3W difference. The idle power usage was much higher than the reference card though. This, however, was not isolated to the Diamond model as the reference card showed a similar increase once overclocked.

Conclusion:

I have been testing various AMD 6800 series graphics cards for the better part of a week now, and I have to say that I am very impressed with what AMD has done. This is not to say that the HD 6800 series graphics cards have ground breaking performance, but at the $179 and $239 price segments, AMD has definitely raised the bar in terms of mainstream performance value. This is especially true in titles that utilize DX11 technologies. The HD 6850 is the more budget friendly of the two cards and as such trims the architecture to accommodate the price. Still, even with reduced Stream processors and a clock frequency of 775MHz, the HD 6850 performed great and in nearly all the tests quite handily outpaced the HD 5830. This makes the HD 6850 and great budget graphics card. The HD 6870 is the more expensive of the two and includes more processing power. This showed in all the tests as the HD 6870 at time rivaled the performance of the HD 5870. With the exceptional performance level of both the HD 6870 and HD 6850, consumers can now enjoy high-end Cypress gaming power for a fraction of the price.

Along with the great performance of the single cards, the HD 6800 series also scale incredibly well when being used in CrossFire. When combined in our tests, the HD 6870 and HD 6850 performed at nearly at the same level as the HD 5970 in some of the benchmarks. Additionally, the two cards in CrossFire had a lower TDP than a single HD 5970, and with a combined price of $418 dollars they are nearly $200 dollars less than the current AMD flagship graphics card. The only game that did not have the two cards performing exceptionally well was Darkest of Days, but this title does not support CrossFire or SLI, so looking at that game's dual GPU performance is not a good indicator of how the cards will perform in the majority of other games on the market.

When it came to overclocking, the HD 6850 and HD 6870 were able to achieve decent results, however the HD 6850 proved to have more overclocking headroom than the HD 6870. The end results in our labs had the HD 6870 clocked 970/1140MHz and the HD 6850 at 920/1170. With these settings both cards showed substantial performance gains, which adds to the overall value of the cards.

Along with great performance the new Barts also include new technologies and one of the more exciting aspects of the 6800 series is the use of dual version 1.2 DisplayPorts. The new ports add support for 3D displays and even allow a single signal to be split among three displays from one connection. This does require the use of a cable splitter but with the ability to use six monitors on the two ports, Eyefininty could eventuality become more accessible for the average consumer. The 3D support on the other hand still seemed to be in the early stages of development. Even though I was shown first hand a working display using a 6800 graphics card paired with a pair of Oakley glasses, it might be some time before 3D is readily available for AMD users. This is mostly due to the lack of supported monitors on the market.

So while AMD seems to have a success on their hands, NVIDIA will not be sitting quietly as the Barts-based cards start to role in. NVIDIA's response to the new AMD Radeon HD 6850 and HD 6870 are price cuts in their current Fermi lineup. To compete against the HD 6850, NVIDIA is reducing the price of the 1GB GTX 460 to $199 and they have even reduced the GTX 470 price to $249. This does make put NVIDIA in a competitive position against the Barts, but with the high-end Cayman GPUs just a month away price cuts might not be enough. However, I am sure they have something in the works to counter the Cayman launch.

Ultimately, the AMD HD 6850 and HD 6870 both perform at levels that rival the high-end performance of the 5800 series, at a substantially lower price tag. The HD 6800 series also includes many new technologies such as DP 1.2, HDMI 1.4a connections as well as improved DX11 performance. The new Barts GPU have whet our appetite for the upcoming Cayman products, and we now can't wait to see what AMD's actual high-end graphics cards can do. Thanks to AMD, this is shaping up to be one exciting holiday season!

Along with the reference cards we were also able to test out an overclocked version of the HD 6870 from Diamond. This card comes with the GPU clocked at 940MHz and the memory bumped up to 1100MHz. These clock speeds increased the performance right of the the box, which usually account for an additional two to four FPS. There were some games though that had the Diamond XOC performing 10FPS better than the reference model. This makes the Diamond XOC an ideal solution for anyone looking for the best out of the box experience.

It is also important to mention that AMD says there will be no shortage of AMD 6800 series graphics cards and that there will be tens of thousands of boards available as soon as the first reviews go live.