1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Does pCARS run better with two GPUs or one GPU?

Discussion in 'Project CARS' started by Billy Pilgrim, Mar 26, 2014.

  1. I'm about to buy all the parts for a new pc to play sims, and especially to play pCARS (and AC, rF2). I've already got three monitors for this too.

    I'd really like to hear how pCARS performs with two GPUs.

    I can't decide whether I should get one GTX 780ti or two GTX 780s.

    What will give the best results with pCARS?

    Your thoughts, experiences on this subject will be most welcome.
  2. Rupe Wilson

    Rupe Wilson
    Keep Yoga real Premium Member

    I don't have Pcars or run in sli but i will do at some point. For me when upgrading get the best i can at the time
    So for me get the single card and in a years time when that card comes down in price you can always get a second card to run in SLI
    that is my plan with my titan in a year or so i will buy a second one.
    all these new sims still need to be optimised from what ive read and seen
    AC works ok with a single titan card on triple screens but i don't max out the settings same with rf2. and the same for R3E
    but in a year or so the sims should be better optimised and i can really have fun if i buy a second card
    it all depends on how much money you have to spend and how you want to use it..

    i may be totally be wrong in my approach, but this is the path i walk :)
    • Like Like x 1
  3. People are having mixed results with SLI and crossfire.
    From what I can gather, SLI performs reasonably well, crossfire, not so good.
    I'm running X2 7950 and depending on the crossfire mode I get good performance and lots of flicker or stutter.
    I would recomend a single card to avoid the hastle
    • Like Like x 1
  4. I just ordered the GTX 780 OC for a small bump in graphics performance. I only run one monitor with games now and I hope to use the consumer version of the Oculus Rift eventually. Any future upgrade beyond that would probably be a single Titan. It seems that the single card solution is the most reliable and maybe DX12 will boost performance down the road to make that more viable with multi-monitor setups.
    • Like Like x 1
  5. So, from what you've understood, regarding SLI, two is better than one in pCARS?
  6. Andy Jackson

    Andy Jackson
    Sponsored by BRUT Premium Member

    A good single card everytime for me. My GTX770 seems to run just about everything maxed out. No stutters and no problems.
    • Like Like x 1
  7. Yes, from what I read two cards (SLI) perform better than one.
    There is a large thread on the pcars forum on setting up a SLI profile and looks like there are few problems, crossfire on the other hand not so good.
    Two cards are a pain in the ass tbh, heat, power, scaling and extra noise.
    • Beer Beer x 1
  8. "pcars forum": You mean the pcars forum here at Race Department? Or at pCARS official WMD forums?

    And (I'm new to pc gaming), what's scaling?

    I understand heat is an issue, but isn't that just a question of setting up the system properly from the start (with a large case, and two fans)? Or ... ?
  9. Yes, the WMD forum, don't think you can access it unless you are a member.

    Scaling refers to two cards getting you better performance, this would be positive scaling.
    Some games do not achieve better performance with two cards, this is refered to as negative scaling.
    All this depends on the game, drivers your setup, pot luck and witchcraft.

    You may also need to consider your psu and if it can handle two beefy GPUs.

    Heat may or may not be an issue but there will be more with two cards.

    I have spend a fortune getting two 7950s to not work in most games, close to £600
    If I had the chance again, I would buy one card.

    Potential performance is good and in benchmarks my system performs well but this does not translate well into all games.

    I would be waiting for release as things are changing daily in pcars.
  10. Thanks for scaling explanation.
    You did point out that CF is worse than SLI although what you say about the massive hassle of multi-GPU does turn me off the whole idea. But I'm planning on SLI so I'm hoping it's gonna be a lot more successful than CF.
    Also I'm mostly looking to playing pCARS and AC and GSC, from what i've read on forums, all three of those games perform better in SLI than single GPU. It's also the demands of three screens that make me think SLI is the best solution for me.
    Which games have been difficult to get going with multi-GPU for you?
  11. I can tell you the following
    U wont be able to run pCARS at maximum settings (1080p @ 60FPS) with a GTX 780ti
    I have it maxed out (except the AA - Dx2X) and im running in Dry @ 1400 between 50 and 80 FPS (depends on track) ... 20 FPS less in Rain ... if i turn the AA to maxium (Ds9x) i have in the same dry conditions around between 28 and 38 FPS (depends on track again)
    In rain im under 18 FPS

    So mmmhh... expect with even the nextgen Gfx (GTX 880) not to run Project CARS at maximum settings @above 60FPS
  12. Those are pretty bad results. I'm very surprised. You get good results in other games at high/max settings?

    Well, that's not good news for me. I've ordered a new pc with two GTX 780 and three monitors.
  13. Always remember this is preAlpha ... So optimiziation will be done until release
    i really think that you get with your ordered rig on a single monitor maximum graphics @60FPS ... with 3 Monitors NOT
  14. My new GPU - a single 780Ti 3GB card - runs about 30% faster in pCARS compared to my 2 x 2GB GTX 680 cards in SLI.
    • Beer Beer x 1
  15. Sounds like the SLI profile isn't working well in pCARS. Hopefully they'll get it sorted out by release.
  16. I see similar improvements across AC, rF2 and pCars. Maybe if it is an SLI issue it will get fixed. Until then I'll enjoy the boost :)
  17. rFactor 2 SLI is completely broken. If Slightly Mad is using any of the same code or engine they were using in Shift 2 Unleashed then pCARS SLI support is broken too. Shift 2 Unleashed does not work properly in SLI. Ironically, the original NFS Shift did work fine in SLI. Assetto Corsa also works fine in SLI but it didn't have a working SLI profile until Jan. 7 of this year, and there's still a bug if you don't use the Shadow Resolution: High setting in the graphics menu then SLI won't work properly. A lot of racing games and sims have trouble with proper SLI support.
    Last edited: May 9, 2014
  18. From the sound of it, they need to do a lot of performance optimization with Pcars as 30-40 fps with high end graphics and CPU wont cut it. If its a next gen DX11 title then it needs to do SLI / CF properly. Its would be ridiculous to not have that kind of support and call yourself a next gen game.
  19. Kjell Eilertsen

    Kjell Eilertsen
    Premium Member

    Have you tried running DX11? Dunno the state of it in pCars atm but I've experienced a performance (aka FPS) increase in some games when enabling DX11. DX11 is supposed to be more efficient than DX9, but it's mostly down to implementation from the developer, Neverwinter Online for instance I get great performance in DX11 but the game crashes ever 5 min to 1 hour. DX9 gives me less FPS and less effects (less pretty), but at least it's stable.
  20. Seriously? For sure i run in DX 11 and even MT ... lol my game crashes after i restarted ~10times