Power, Temperature, & Noise

As was the case with gaming performance, we’ll keep our running commentary thin here. The Radeon HD 6950 1GB is virtually identical to the 2GB card, so other than a few watts power difference (which can easily be explained by being an engineering sample) the two are equals. It’s the XFX Radeon HD 6870 Black Edition that has caught our attention.

Radeon HD 6800/6900 Series Load Voltage
Ref 6870 XFX 6870 Ref 6950 2GB Ref 6950 1GB
1.172v 1.172v 1.1v 1.1v

While the XFX 6870 has the same load voltage as the reference 6870, between the change in the cooler and the higher core and memory frequencies power usage still goes up. Under Crysis this is 11W, and under FurMark this expands to 16W. Unfortunately this factory overclock has wiped out much of the 6870’s low power edge versus the 6950, and as a result the two end up being very close. In practice power consumption under load is nearly identical to the GTX 460 1GB, albeit with much better gaming performance.

Meanwhile this is one of the few times we’ll see a difference between the 1GB and 2GB 6950. At idle and under Crysis the two are nearly identical, but under FurMark the 1GB reduces power consumption by some 12W even with PowerTune in effect. We believe that this is due to the higher operating voltage of the 2Gb GDDR5 modules AMD is using on the 2GB card.

As far as temperatures go both cards are in the middle of the pack. The vapor chamber cooler on the 6900 series already gives it a notable leg up over most cards, including the XFX 6870. At 41C the XFX card is a bit warm at idle, meanwhile 78C under load is normal for most cards of this class. Meanwhile the 6950 1GB and 2GB both perform identically, even with the power consumption difference between the two.

Last but certainly not least we have our noise testing, and this is the point where the XFX 6870 caught our eye. The reference 6870 was an unremarkable card when it came to noise – it didn’t use a particularly advanced cooling design, and coupled with the use of a blower it ended up being louder than a number of cards, including the vapor chamber equipped Radeon HD 6970. The XFX 6870 reverses this fortune and then some due to XFX’s well-designed open-air cooler. At idle it edges out our other cards by a mere 0.1dB, but the real story is at load. And no, that’s not a typo in the load noise chart, the XFX Radeon HD 6870 Black Edition really is that quiet.

In fact at 41.4dB under load, the XFX 6870 is for all intents and purposes a silent card in our GPU testbed. Under load the fans do rev up, but even when doing so the card stays below the noise floor of our testbed. Compared to the reference 6870 we’re looking at just shy of a 14dB difference between said reference card and the XFX 6870, a feat that is beyond remarkable. With the same warning as we attach to the GTX 460 and GTX 560 – you need adequate case cooling to make an open-air card work – the XFX Radeon HD 6870 Black Edition may very well be the fastest actively cooled quiet card on the market.

Meanwhile for the Radeon HD 6950 1GB and 2GB, we’re once again left with results that are nearly indistinguishable. Under load our 1GB card ended up being .6dB quieter, an imperceptible difference.

The Test & Gaming Performance Final Words
POST A COMMENT

111 Comments

View All Comments

  • ibudic1 - Wednesday, January 26, 2011 - link

    you can unlock the 6950 to a 6970 for free.

    just google: unlocking HD6950

    and the NVIDIA value proposition goes down the toiled. End of discussion.
    Reply
  • Ananke - Wednesday, January 26, 2011 - link

    So much agree!!!
    5850 2Gb is the way to go.
    Reply
  • Ananke - Wednesday, January 26, 2011 - link

    6950 :) I mean Reply
  • Mr Perfect - Wednesday, January 26, 2011 - link

    None of the sites I frequent have said anything about a reduction in texture filtering quality with the new Catalyst versions. Could someone post some links to articles about the issue? Why didn't Anandtech mention it, anyhow? Reply
  • silverblue - Wednesday, January 26, 2011 - link

    Toms did something...

    http://www.tomshardware.co.uk/radeon-catalyst-imag...

    I believe it has been mentioned that any such performance enhancements have been rolled back, so to speak.
    Reply
  • Mr Perfect - Thursday, January 27, 2011 - link

    Hmm, interesting. Tom's points back to an Nvidia post on the issue( http://blogs.nvidia.com/2010/11/testing-nvidia-vs-... ), who themselves quote four review sites I'm not familiar with. Guess I'll check out those sites and see what they're reporting. Reply
  • silverblue - Thursday, January 27, 2011 - link

    I think they were German sites or something? It's been some time since I read this. Reply
  • ezinner - Wednesday, January 26, 2011 - link

    How about putting the price of the cards in the benchmarks? It isn't enough to know how fast a card is, but rather at what cost. Reply
  • swaaye - Wednesday, January 26, 2011 - link

    8X SSAA :D Reply
  • GTVic - Wednesday, January 26, 2011 - link

    This looks nothing like the black edition sold at ncix or newegg? This one has two fans so what is the difference? Reply

Log in

Don't have an account? Sign up now