Results 1 to 10 of 10
  1. #1
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    Maximus XI Extreme Dimm.2 and pci lanes

    So i have a 1080ti ftw3 gpu in my pcie_1 slot
    and i also use a pci 4x usb card for oculus rift. in my pcie_3 slot as i assumed this used chip set lanes?
    and im using at the moment the dimm.2 card with a NVME drive as my boot drive.

    for whatever reason i'm getting my gpu as x4 ( in pcie_1 slot )
    and x2 or x4 both work in pci3 for the usb card, i honestly dont know if it matters either way, i think the card will work with x2? preferably to keep my sata5/6 slots.
    here's a link to the card speicifially i use for usb: https://www.amazon.com/StarTech-com-....0+4+dedicated

    i thought the way i had it setup i would get to use 2 nvme drives in the dimm.2 card slots and the gpu would be x8/x8? am i wrong? is each dim slot x8? im so confused. doesnt pci slot 3 go off the chipset? only slot 1 and 2 use cpu lanes?

    i have no issue with my gpu in x8 but i'd prefer it not to be in x4 mode for sure.

    what can i do to remedy this?

    thanks guys! if u need more info please just ask.

    system:
    9900k
    maximus extreme XI
    boot drive samsung pro 970
    and a gtx t1080ti ftw3 black
    custom water loop
    corsair dominator pro ram 32gb
    Last edited by Peregrinus; 02-07-2019 at 06:11 AM.

  2. #2
    ROG Guru: Orange Belt Array G75rog PC Specs
    G75rog PC Specs
    MotherboardR VI Apex
    ProcessorI9-7900X
    Memory (part number)64GB Gskill Trident Z
    Graphics Card #1AMD Radeon VII EKWB water block
    Graphics Card #2Waste of PCI lanes in NVME environment
    Sound CardStock
    MonitorLG 34" Ultra Wide3440x1440
    Storage #14ea 960 Pro 2TB, 2ea 970 Evo 2TB
    Storage #21ea 960 Pro 1 TB, 1ea 970 Pro 1TB
    CPU CoolerEKWB CPU, Swiftech Res/pump, 400mm Rad
    CaseThermaltake View 91
    Power SupplyNZXT Hale 90 1200W
    Keyboard Logitech G910
    Mouse Razer Ouroboros
    OS W10 64 1809, 1903, Ubuntu Linux
    Network RouterNetgear R9000 + 4ea R9000 AP's, 10 Gb Switch
    Accessory #1 Hyper M.2 X16 V2
    Accessory #2 10GB network via Intel 550 Nic
    Accessory #3 2 10GB Asustor NAS 7000 series

    Join Date
    Jan 2013
    Reputation
    13
    Posts
    252

    The pcie slot allocations and dimm card usage are explained in your user manual.
    Pciex16_1 and pciex16_2 share the 16 available cpu lanes.

  3. #3
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    Let me reiterate,

    At the moment I am using PCI slot 1 for the 1080, I skipped pci2 and used slot 3 for the USB card.

    So slot 2 is empty. The graphics card should be running x8 am I wrong? This is what I am not understanding.

    Using dim.2 with nvme, gpu in slot 1 slot 2 empty slot 3 has USB card.

    Slot 3 should run off of the PCH Lanes and not the CPU correct? Why is the gpu being limited to x4.

    I also updated to 0805 bios last night hoping maybe that would help, but didn't change anything.

  4. #4
    ROG Enthusiast Array
    Join Date
    Mar 2015
    Reputation
    10
    Posts
    72

    Quote Originally Posted by Peregrinus View Post
    Let me reiterate,

    At the moment I am using PCI slot 1 for the 1080, I skipped pci2 and used slot 3 for the USB card.

    So slot 2 is empty. The graphics card should be running x8 am I wrong? This is what I am not understanding.

    Using dim.2 with nvme, gpu in slot 1 slot 2 empty slot 3 has USB card.

    Slot 3 should run off of the PCH Lanes and not the CPU correct? Why is the gpu being limited to x4.

    I also updated to 0805 bios last night hoping maybe that would help, but didn't change anything.
    Can't tell you why it's x4. But I believe the dim.2 slot uses cpu lanes...(if that's the slot near the ram slots)

  5. #5
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    I do have the gpu going through a riser card so I can vertical mount it, I will try cleaning the cable and contacts and reseating it tonight, maybe that could be effecting something.

    But as far as I can tell on paper, it "should" be running the gpu and the dimm.2 in x8/x8 mode. I don't get why I'm getting x4.

  6. #6
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    ok guys update, i reseated the gpu with the riser card.

    i also took out the dimm.2 slot entirely, so at this point pcie slot 1 has my 1080ti

    and slot 3 has the usb card running in x2

    and im STILL getting my gpu running in x4 from gpu-z with it loaded up.


    at this point am i to think that the issue is the riser card or what? it should DEF be running in at least x8 now.

  7. #7
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    update #2.

    removed dimm.2 and put gpu directly in slot 1 eliminating riser card, which took me 2 hours because i had to redo my water lines.

    card now runs in pci 3.0 x 16 so apparently it was the riser card. oh Well, problem solved. thanks guys!

  8. #8
    ROG Member Array
    Join Date
    Dec 2018
    Reputation
    11
    Posts
    5

    Would it be possible to run the DIMM.2 slot from the PCH bus instead and disable the third PCIE slot?

  9. #9
    ROG Member Array
    Join Date
    Jan 2014
    Reputation
    10
    Posts
    9

    I dont think so, pretty sure its tied directly to the cpu lanes.

    i still want to try to get 2 ssds into the dim slots and keep my 1080 at x8, i havn't tested if this works yet.

    pretty sure to use both dim slots AND keep my gpu at x8 though i have to use the second pci slot though, so to test, id have to tear apart my loop, yet again.

  10. #10
    ROG Guru: White Belt Array
    Join Date
    Sep 2013
    Reputation
    49
    Posts
    101

    I have this working
    pcie slot 1 GPU X8
    pcie slot 2 empty
    pcie slot 3 Intel ssd card x4
    DIMM.2.1 and 2: 2 ssd (x?)
    PCH ssd under cover slots: empty, too hot and terrible placement.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •