Skip to main content

PCIe And CrossFire Scaling: Does Nvidia's NF200 Fix P55?

But Can NF200 Help X58, Too?

There’s been some discussion among Tom’s Hardware staff about whether the CrossFireX performance gains seen by adding the nForce 200 bridge to the P55 platform were simply a matter of accessing the processor's faster PCIe 2.0 lanes. Beyond the potential division of the CPU’s 80 Gb/s PCIe bandwidth across three cards, possible improvements include the ability of the cards to communicate with each other at up to 40 Gb/s (at x8 mode for three cards) and, more importantly, the likelihood that all of the cards connected to the NF200 are receiving the same data from the CPU (the performance equivalent of 32-lanes from the processor's 16). Surely the NF200 could also be used to provide the X58 chipset with enough additional lanes to support three graphics cards with the full set of 16 pathways, but would those extra lanes provide the 4% performance difference we noticed between x8 and x16 slots in our PCIe Scaling Analysis?

We needed to know whether or not the nForce 200 bridge’s extra lanes could add any "punch" compared to our X58 motherboard’s chipset-supported x16/x8/x8 configuration, and we also wanted to see how much performance loss would be incurred by using a less-expensive, x16/x16/x4 mode X58 motherboard. The X58+NF200 configuration came via MSI’s Eclipse Plus with its only BIOS release (V1.1), while the Asus P6T (BIOS 0801) represents the reduced-cost X58 option.

Our Far Cry 2 benchmark set was picked as the “most typical indicator” of gaming performance.

The NF200-equipped MSI Eclipse Plus beats the X58 native solution at medium resolutions, but the performance becomes identical at 2560x1600. The highest resolution is also where Asus’ x16/x16/x4 configuration falls behind, but not by enough to discourage most buyers from looking towards this less expensive motherboard as a potential value leader.

The NF200 advantage for X58 motherboards disappeared when we enabled AA. Because it’s cheaper than all but the EVGA P55 SLI motherboard, Asus’ P6T continues its hold on value.

  • liquidsnake718
    Score One for the X58. The NF200 should help the P55 however but at an added cost. ALl in all interesting to see that Nvidia has been busy making this for the onboard and motherboard vendors instead of focusing on the GF100. I am sure they are really strategizing and letting AMD/ATi get the upper hand for a short time as their target market for business is also reaching a wider market in motherboard vendors. Then when GF100 comes out, ppl will see the type of quality GPUs that are meant to please the eye and take on the best and most demanding apps/games/HD content.
    Reply
  • outlw6669
    With dual CrossFire/SLI (where it really matters most) it is kinda hard to fix something that ain't broken.

    Nice gains with three way though.
    Pretty sure if you have $1200 to dump on GPU's you would have gotten the proper platform in the first place...
    Reply
  • falchard
    MSI wins again.
    Reply
  • apache_lives
    well there you go, high end x58/1366 systems with a high end price offer the higher performance, and pushing a mid-range 1156 platform to high end performance requires extra exotic equipement/chips to do it - no new news here
    Reply
  • apache_lives
    outlw6669With dual CrossFire/SLI (where it really matters most) it is kinda hard to fix something that ain't broken.Nice gains with three way though.Pretty sure if you have $1200 to dump on GPU's you would have gotten the proper platform in the first place...
    Exactly my point +1000
    Reply
  • elmo_gr
    Testing should have been done with 5670's
    Reply
  • mfarrukh
    Just Give us the Dman FERMI already
    Reply
  • 2shea
    It proves again that the x58 is stock the best performer albeit not very much in comparison with the buffed up p55 gf200 chipset. But in practical mode, I don't see the big wins with triple vs. dual gpu's. Moreover I probably won't even go dual videocards because of the relative high fps which don't matter much, 60+ is more than enough for any game on a flatscreen monitor. 30+ is mostly enough for most single player games.
    It DOES however prove that the chip gives a reasonable gain if games are going to demand more then they do now. The only games available that can really max out anything are crysis, WIC, total commander and that's pretty much all.
    For the rest pretty good article though
    Reply
  • Hupiscratch
    I prefer to use the remaining 4x PCI-e 2.0 lanes of the X58 for a Fusion-io Duo drive. Can you imagine?
    Reply
  • a4mula
    I bow to you Crashman. This was the granddaddy of all p55 reviews and I openly admit to standing corrected. I honestly didn't believe the NF200 could pull it off, but I was obviously wrong.

    I wish this review had come a week earlier, I would have gone 1156 over 1366 but at least it finally showed up. The last vestiges of X58's hold over P55 have been erased in my mind.

    Now you can move on to figuring out SATA 6Gb/s for us. I know, I know I'm never pleased. Great work.

    Reply