Triple-GPU Scaling: AMD CrossFire Vs. Nvidia SLI

Features
By Thomas Soderstrom
published

Two GPUs are great, but are three that much better? When it comes to multi-card scaling, can AMD finally beat Nvidia? Who really needs this much performance? We loaded a super-fast system in single-, dual-, and triple-GPU configurations to find out.

Average Performance Analysis

The single Radeon HD 6950 looks fairly weak in average 1680x1050 performance, but superior dual-GPU scaling allows it to nearly catch the GeForce GTX 570. That scaling advantage goes away when three cards are installed, yet even Nvidia’s winning third card is almost useless at this medium resolution.

The scaling results we saw at 1680x1050 are repeated at 1920x1200. AMD’s card is far cheaper than Nvidia’s, so value seekers who game at this resolution will get their best value with a pair of Radeon HD 6950s.

Any Radeon HD 6950 CrossFire solution beats any GeForce GTX 570 SLI configuration at 2560x1600, regardless of whether two or three cards are used. This is probably the only resolution in today’s test that really matters, since a single card will pass most tests at anything less. Additionally, 2560x1600 has a similar pixel count as three 1280x1024 displays, so this is “just the beginning” for anyone planning to run in Eyefinity or Surround mode.

Thomas Soderstrom
Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
163 Comments Comment from the forums
  • amk09
    :( i wish i could afford that
    Reply
  • tacoslave
    wow even though a 6950 is weaker than a 570 it dominates at higher resolutions eyefinity here i come.
    Reply
  • scrumworks
    Impressive and unexpected results. Speculations that crossfire scaling is worse than SLI can finally be put into rest.
    Reply
  • aznguy0028
    scrumworksImpressive and unexpected results. Speculations that crossfire scaling is worse than SLI can finally be put into rest.Not true, I would have liked to see more games on the test. The choices were too limited for my taste. For example, everyone knows that Crysis is heavily Nvidia favored, so it's not surprising to see those results in the least.

    Here's another article on the 68xx series in Xfire
    http://www.xbitlabs.com/articles/video/display/radeon-hd6870-hd6850-crossfirex.html#sect0

    Xfire scaling was found to be 100% on 10 or the 19 games they tested, and remaining very high on the others. Nvidia and ATi seems to trade blows at different games tested, but it is evident that Ati has stepped up their Xfire drivers int he 6xxx series.
    Reply
  • aznguy0028
    scrumworksImpressive and unexpected results. Speculations that crossfire scaling is worse than SLI can finally be put into rest.I misunderstood what you meant. But yes, xfire/sli scaling has improved alot this generation :)
    Reply
  • liquidsnake718
    Now im thinking if i should even spend on a now older 5850 to crossfire on my X58.
    Reply
  • bavman
    Its really cool to see amd stepping up their game. Multigpu scaling used to be only good on nvidia, but now amd is beating them. Though i feel that more games should be tested before a firm conclusion should be drawn.
    Reply
  • _Pez_
    I would get two HD 6870 for a mobile crossfirex gaming rig ! :D
    Reply
  • anubis44
    No! Don't buy a 5000-series card to crossfire. The 6000 series cards are essentially all better at crossfire scaling than their predecessors. This performance advantage will likely only increase with additional driver revisions and better 6000-series optimization support than for older products.
    Reply
  • Maziar
    Great review ! It's good to see AMD did a lot of work on CF scaling.
    Reply