Issue(s) with PCIe 4.0 & PCIe extension cables...?

Discussion in 'Small Form Factor Systems' started by Boil, May 21, 2019.

  1. Boil

    Boil [H]ard|Gawd

    Sep 19, 2015
    Just curious how the move to PCIe 4.0 for upcoming X570 motherboards will affect those using a chassis that requires a PCIe extender cable...?

    This may also impact any of the older AM4 motherboards that can (with proper BIOS update) run PCIe 4.0 in the first PCIe slot...?

  2. IdiotInCharge

    IdiotInCharge [H]ardForum Junkie

    Jun 13, 2003
    Might just renegotiate to PCIe 3.0? Might be user selectable?
    So long as that's an option, shouldn't be a problem.

    If PCIe 4.0 is needed, then a chassis adjustment may be needed too.

    [I do have an ITX system that uses one myself...]
  3. SaperPL

    SaperPL [H]ard|Gawd

    Aug 31, 2014
    Does it really matter to anyone in gaming? Right now I think we're barely using 8 lanes of pci-e 3.0 bandwidth, techpowerup did this kind of test multiple times and gamers nexus did one as well. Pci-e 4.0 will matter for bifurcation and nvme storage only, unless you are doing some scientific/crypto cracking I think.

    I'll dig in this subject when there's actually 4.0 board and GPU reviews.
    Last edited: Jun 3, 2019
  4. Fasda

    Fasda n00b

    Mar 17, 2019
    I'm hoping there'll be bifurcation controllers that splits up pci-e 4 lanes into twice that amount in pci-e 3 lanes.
    But knowing the main manufacturers of such they'll be obscenely expensive and require a NDA that'll feel like making a deal with the devil is a great idea.
  5. snaggletooth

    snaggletooth [H]ardness Supreme

    Aug 16, 2005
    Not to revive an old thread, but I'm reviving an old thread.

    I just moved my system from an old Antec case to a Fractal Design R6 and added their PCIE riser.

    I'm running NVME Raid with 2 Sabrent drives and I'm getting video errors while using the Fractal Design riser. First boot reset my BIOS. Reestablished my settings and after a few video card related errors I'm able to get to Windows (I'm here now on the system)

    That's the only hardware change other than the AIO I also added for poops and laughs.

    I wont be posting again tonight, but I'm going to run a couple of Firestrike runs, if it lets me and see where I'm at. CPU-Z and GPU-Z are reporting normally.

    Hopefully no magic smoke is released.
    IdiotInCharge likes this.
  6. snaggletooth

    snaggletooth [H]ardness Supreme

    Aug 16, 2005
    Was able to complete a run of Firestrike - my score was more than halved from ~23000 to just below ~11000. Also noticed my GPU fans were not spinning during the entire test - fun to watch. Rechecked my power connections from the PSU to GPU, re-ran the test and had the same result.

    Shut it down, removed the riser and plugged the GPU back in directly. Problem solved.

    So the fact that Fractal Design's PCIE riser is listed as only PCIE 3.0 compatible may have some bearing on these results, but I would have assumed that the GPU would run on a PCIE 3.0 adapter just fine, since there's no way it's saturating the bus along with the pair of NVME M.2 drives.

    TL;DR - Fractal Design's PCIE 3.0 Riser isn't compatible with Gigabyte X570 Gaming X motherboard while using both M.2 NVME slots - for some reason. OR I have a defective riser - which I don't believe is the case.
  7. sirmonkey1985

    sirmonkey1985 [H]ard|DCer of the Month - July 2010

    Sep 13, 2008
    are you forcing the slot into pcie 3.0 in the bios? if not try that since it sounds like the boards trying to force pcie 4.0 and the signal integrity on the risers too crappy to handle it. otherwise yeah it's possible the risers bad which isn't as uncommon as you might think. the drives won't matter since 1 drive is direct to cpu and the other drive is running off the chipset along with the lower pcie x16 slot(x4 actual) and 1x slots.