Multi-monitor SLI Users Rejoice!

Hey guess what? If you've got SLI and two monitors, you no longer have to turn SLI off to use both monitors. It's been 4.5 years since the introduction of SLI and we finally have support for a feature that should've been there from the start. Granted AMD/ATI/SnowWhite didn't have support for this multi-GPU/multi-monitor setup until last year with the Radeon HD 3870 X2 so it's not purely a NVIDIA thing. If you run a full screen 3D application your second display will go blank and come back as soon as you've quit your application, whereas in the past you had to go into the NVIDIA Control Panel, enable SLI, run your 3D app/game, go back in, disable SLI and then you'd get your second display back. In the new driver you don't have to do any of this - sweet.

While NVIDIA's driver supports up to 6 monitors, for SLI to work you can only have displays connected to the master card in SLI with a maximum of two monitors connected. So if you want to have more than 2 monitors and support SLI you'll either need three cards or you will still need to disable SLI to get your non-master SLI card to output video.

The multi-monitor driver interface also got an update in a very sensible way; you can now select which monitor will receive the display when running in SLI mode, it's no longer tied to a fixed output on your video card. Hooray for flexibility!

While selecting the SLI Focus Display is done in the SLI settings menu, when adjusting your multi-monitor setup, there is an indicator that lets you know which display is the SLI focus display. It's a little green square in the corner. Check it out.

When we played around with it, the primary display had to be the SLI Focus Display when the primary display was connected to the SLI bits. The only way to make the primary display (the one with the start menu and all that stuff) not the SLI Focus Display was to run it off a second card. At which point, the SLI Focus Display could still be selected if two monitors are connected to the SLI hardware.

Another multi-monitor feature to note is that 3 games (Flight Simulator X, World in Conflict and Supreme Commander) are also accelerated across multiple monitors. We would really like to see all games supported across multiple monitors (without the use of one of Matrox's DualHead2Go or TripleHead2Go boxes), but there are still some difficulties with rendering a game across multiple displays when the game does not expect to have its framebuffer split. It is good to see that NVIDIA is at least extending support of new features in new drivers to games whose developers have specifically included multiple monitor support.

The extensiveness of the SLI and mulit-monitor flexibility is nice, and we are definitely glad to finally have all of this working. It's been a long time in coming, but we are glad that it's finally here.

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  • Finally - Friday, November 21, 2008 - link

    I could have taken you seriously if it wasn't for your child-like pronounciation of that green firm's name.

    Do you also write about "Micro$oft"?
  • Paratus - Thursday, November 20, 2008 - link

    I always see both camps complaining about the state of each companies drivers.

    IMHO I'll take AMDs bad drivers every month instead of NVs bad drivers every whenever they decide to release them.

  • ggathagan - Thursday, November 20, 2008 - link

    We would like to have seen the performance gains NVIDIA talked about. While we don't doubt that they are in there, it is likely we just didn't look at the right settings or hardware.

    If NVIDIA claims "Up to 38% performance increase in Far Cry 2", they should be able to tell you the exact circumstances where that 38% increase can be seen. If it's reproducible, great. If not, they're lying and should be called on it.

    As for PhysX: I'm all for realizing its potential, but Mirror's Edge strikes me as having PhysX simply for the sake of having Physx.
    Granted, it's just a trailer, but I wasn't that impressed with the look of the game. It looked as if they spent their time on the Physx and ignored the character modeling. The arm/body movement looks rather bizarre.
  • Kode - Thursday, November 20, 2008 - link

    Although I agree that some ATI/AMD driver updates aren't that good, the good thing about a monthly release is that when you have a small bug/glitch in a certain game, this can be updated in a month. If you have the same thing on a NVIDIA card, you don't know when to expect a new driver, and so you are stuck with it untill the next driverrelease unless they release a hotfix or perhaps beta. But installing hotfixes/beta's isn't done often by regular people. Reply
  • Casper42 - Thursday, November 20, 2008 - link

    Title says it all. Driver enhancements and TELSA are great and all, but where are the darn die shrinks?

    I was really hoping nVidia would have their stuff together and have released the GTX 279/290 or whatever they decide to call the 55nm parts when Intel released the i7 processors. When gamers are blowing $1000+ on a new Board/Chip/RAM, whats another $600 for that top of the line nVidia card?

    After all, wasnt the point of allowing SLI on x58 to sell more cards?
  • Casper42 - Thursday, November 20, 2008 - link

    The HPC Market seems to be going more and more toward Blade servers these days as you can cram an awful lot of computer power into a 10U space with hardware from 2 or 3 different vendors.

    I am curious if nVidia is working with HP or Dell or IBM on making a special Blade version of their TESLA cards. The expansion cards in the HP c series are very small which may prohibit TESLA from physically even fitting into the Blade server. BUT, they also have a way of channelling PCI Express lanes into an adjacent blade slot (for instance, to support their "Storage Blade") so if TESLA won't fit inside the blade itself, why not put together a TESLA blade that contains 2/3/4 Cards and connects to the adjacent blade server.

    This would allow you (for instance) to take an HP c7000 chassis and put 8 BL460c Blades with up to 2 Xeon 54xx chips, 64GB of RAM (assuming 8GB DIMMs), and then have 2-4 TESLA cards attached to each, and cram all that into a 10U space. At a minimum that would be 16 Processors, 256GB of RAM (32GB/node) and 16 TESLA Cards.

    You even get your choice of 10GB Ethernet or Infiniband to connect all the nodes.
  • Spoelie - Thursday, November 20, 2008 - link

    This is the first time I've seen someone complain about AMD's driver mantra.

    AMD provides a constant evolution in their drivers, it's the users choice to update the driver or not. You can not fault them for providing lots of updates. Their readme is also very clear and concise in what is fixed and what is not.

    The possible sacrifices do not outweigh the advantages IMO. That comment was a bit of a potshot
  • kilkennycat - Thursday, November 20, 2008 - link

    For at least the last 5 years, ATi's drivers have periodically had the spotty reputation that the next update fixes a bunch of problems with the latest games, but then has newly introduced brand-new problems with earlier "legacy" games. Seemed as if they rushed QC, with only a handful of the latest titles. And for an obvious reason.... the burden of a monthly release cycle is no help in enabling thorough QC at all !!! Much better if the offical releases were at least 3 months apart, with beta updates for the "brave" to try out. The 'next driver breaks something not previously broken' problem was particularly bad when ATi transititioned their architecture with the introduction of the X1800 series. Recently, this ATi legacy problem has got much, much better, but they seem to have slid backwards recently. Reply
  • DerekWilson - Thursday, November 20, 2008 - link

    We have complained about AMD's driver development issues in the past. But we always try and keep it as fair and neutral as possible.

    If all things were equal, I would agree that "you can not fault them for providing lots of updates" ... but that is not what they do.

    NVIDIA regression tests with hundreds of games for every driver release. In fact, comprehensive regression testing was one of the major reasons NVIDIA acquired 3dfx back in the day.

    AMD only regression tests with 25 games. These 25 games change with driver versions so that over time they'll cover many games. The problem is that this doesn't work well. for example ...

    Let's say some x.y driver is regression tested with ... let's pick bioshock. The next month, bioshock falls off the list and x.(y+1) breaks crossfire with bioshock. crossfire isn't as popular as single card performance so there aren't as many users to complain and it will either take them adding bioshock back to their regression test list (which could be never or 6 months or a year), or a large hardware review site will need to go test it an publish an article on how broken it is only to get a hotfix driver 2 days later that fixes the issue.

    that happened by the way. and not only with bioshock. it has happened with other games as well, and most of the time it is an issue that affects crossfire. sometimes its other bugs, but multi-GPU support is the thing that seems to be at highest risk in our experience.

    this is not an infrequent problem.

    and lets say you find a bug in the recently released 8.11 -- no lets say AMD finds a bug in 8.11 ... It will not be fixed until at least 9.1 as they can't push 8.12 back to include more fixes. until then, if its a big name title that has a fix, AMD will put out a hotfix. But then you've got to use a non-WHQL version of 8.11 for upwards of two months, even if there are features in 8.12 you want/need.

    We are currently in a situation where we have to stick with an 8.10 + hotfix until 8.12 comes out.

    I am very conservative in my articles about mentioning problems with driver teams. Driver work is tough, and reviewers tend to hit many more problems than the average gamer. We test much more software on a wide variety of hardware and are more prone to running into issues. While the problems do exist for end users, it's always just a subset of users at a time. It has to be that way to some extent no matter what (there will always be tradeoffs made), but AMDs trade offs do impact us quite a bit. And I also feel like they cut too many corners and make too many tradeoffs to the point where it negatively impacts too many end users. If we hit more problems with one vendor than another, that is a very relevant bit of information for every consumer. Even if it isn't of the same magnitude it is for us, it's still an issue.

    Thus, I am aware that my view of AMD driver development will be more negative than most users out there. But it does still negatively impact end users in a bigger way than NVIDIA's approach in general (though NVIDIA's execution isn't always spot on either).

    Here's the best way I can put it.

    If you find an AMD driver that works, stick with it. Don't change drivers unless something is broken that got fixed that you need. Upgrading when not necessary will likely break something else that you might find you needed.

    On the contrary, I would never recommend against upgrading to an NVIDIA WHQL driver. They are much better about not breaking things that have previously been fixed and are much more hardened by the extensive regression testing. All the fixes that go into one driver (beta or WHQL) will be included in the next beta or WHQL driver, unlike with AMD and their multiple trunk or overlapping branch system or whatever you want to call it.

    There are simply few to no real advantages (other than for marketing purposes) with AMD's driver development approach, so if there are negatives at all they've already outweighed everything else.
  • JonnyDough - Friday, November 21, 2008 - link

    Care to explain to me what happened to Neverwinter Nights 2 and Nvidia then? It doesn't work. Reply

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