PCI Express 2.0 usefullness

Discussion in 'Architecture and Products' started by MistaPi, Nov 14, 2008.

  1. MistaPi

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    Besides multi-cards solutions and value cards with not so much memory, will PCIe2.0 have a impact?
    Will GPGPU useage (CUDA, ATi Stream) make use of PCIe2.0 bandwith in games in the foreseeable future?
     
  2. Albuquerque

    Albuquerque Red-headed step child
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    Bandwidth needs always increase. If they didn't, we wouldn't have moved from 8-bit to 16-bit ISA cards. We wouldn've have picked up vesa local bus. We would have never seen PCI, or PCI-66, or PCI-X, or PCI-E, or now PCI-E 2.0...

    In other words, just because consumer-grade usage isn't fully utilizing it doesn't mean it can't be utilized.
     
  3. Tim Murray

    Tim Murray the Windom Earle of mobile SOCs
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    A lot of CUDA apps see a very significant performance increase from PCIe 2.0. There are ways to minimize its impact with CUDA, but more bandwidth never hurts. (Of course, there are plenty of other apps, such as NAMD, where PCIe bandwidth basically doesn't matter at all.)
     
  4. Npl

    Npl
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    I think the real benefit is not for GPUs (not for a long time atleast), but faster 1xPCIe and 4xPCIe Slots. On AMD-Chipset this also doubles bandwidth between North/South bridge.
     
  5. Shtal

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    I think they should increase PCI-E communication bus speed to 200MHz. :) (100MHz / 133MHz is boring :( )
     
  6. Davros

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    I just hope the people in charge of the pci-e standard care about compatibility
    so far they've failed
    agp wasnt backwards compatible with earlier versions of itself (try putting a 8x agp card in a 1x or 2x slot)
    pci-e 2.0 isnt compatable with pci-e 1.0a
    next time a new gfx slot is introduced they should think about future needs and try to build some future proofing into it
    is it really too much to ask
     
  7. Shtal

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    It worked for me, I run test with ATI HD3870, it worked but slow. Intel MB + 915 chipset
     
  8. Davros

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    iirc ati knew about the problem so their cards boot in pci-e 1 mode and switch to pci-e 2 mode when the drivers are loaded
     
  9. MistaPi

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    To put it a another way, I have a 4870x2 and a mainboard with Intel P35 chipset. Should I upgrade to P45?
     
  10. Davros

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    I'd say no
    check some benchmarks first
     
  11. Berek

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    I was all ready for purchasing DDR3 and an Extreme CPU for my latest system, when I did further research and realized it would have been a complete, absolute waste of money.

    Figure out what you want the computer for at the maximum, check the benchmarks for that level, and then you'll know what you need.

    And I agree, P35 is just fine. P45 is simply a tweak, FSB speed bump here, power savings there... nothing to write home about.
     
  12. Bouncing Zabaglione Bros.

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    No. If you were buying mainstream today, I'd go for P45, but I've not seen one review that said P45 was worth upgrading from a half-decent P35. There's just not enough benefit to splash out on new P45 motherboard unless you're having problems with your old P35.
     
  13. Shtal

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    I run (PCI-E 1.1) P35 motherboard with 4GB DDR2-800MHz 4-4-4-12 and my uncle has (PCI-E 2.0) X38 motherboard with 2GB DDR3 1800MHz 8-8-8 timing "I think"
    He was telling me it is super fast, I knew - it was not a huge difference and did not worth the extra money, that was back when DDR3-1800MHz and X38 just came out.
     
  14. Blazkowicz

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    alright.
    I'll add that the industry seems to take care of it in advance. be it sata, AGP 4x, AGP 8x, PCIe 1.0, new ddr tech etc., when it's introduced it doesn't matter, at any time you don't have to care whether you get gen or gen+1.

    ddr2 didn't matter when introduced, but dual channel ddr2 is useful for quad cores now. likewise ddr3 is useless now but may be more useful with six core, IGP etc.

    There are exceptions such as sdram on pentium 4, maybe PCI for some raid scenarios on consumer mobo back then. But PCIe 2.0 will IMO only matter when 3.0 is out and the problem is moot.
    except maybe for that CUDA stuff, I was writing this thinking more of gaming performance..
     
    #14 Blazkowicz, Nov 16, 2008
    Last edited by a moderator: Nov 16, 2008
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