Motherboard can’t see all GPUs?

Discussion in 'Video Cards' started by StupidDream, Sep 12, 2018.

  1. StupidDream

    StupidDream n00bie

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    i have an Gigabyte ga-h61m-d2s
    I tried installing one RX 580 in the 16 X slot, and an additional RX 580 (for mining) in a 1X slot using a riser. However The system simply does not see the second GPU, however if I use both cards on risers it sees both GPUs just fine which is fine for just straight mining. I think I might be running out of PCI express lanes

    Currently I only have a Celeron g530 installed which I have read only has 16 lanes... but I have a e3-1220 Xeon on the way that Intel says has 20 lanes... I’m thinking this should solve the problem any ideas?
     
  2. kirbyrj

    kirbyrj Why oh why didn't I take the BLUE pill?

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    Check the manual to see how the lanes are configured when certain processors are installed. Seems like a good bet that the video card is using all of the PCIe lanes when installed directly in the slot. If you're just using it for mining, then just use two risers and save the money over buying a 1220.
     
  3. StupidDream

    StupidDream n00bie

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    Well that’s just it I plan to mine on it most of the time, but I would like to use one of the cards for gaming when I decide to play games which is actually why I was picking up the 1220(which I bought used for $32 shipped)
     
  4. StupidDream

    StupidDream n00bie

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    Well sure enough I was right, as soon as I installed my $32 new to me E3-1220 3.1ghz I was able to install one GPU in the 16 X lot and run an additional GPU on a 1X riser. This combo along with 16 gigs of RAM and a I was able to install one GPU in the 16 X lot and run an additional GPU on a 1X riser. This combo along with 16 gigs of RAM and a solid-state hard drive should work wonderful n SSD For playing games (on a single 22” lcd, not running at crazy resolutions) and mining.
     
  5. elite.mafia

    elite.mafia Broke Back [H]

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    Can you switch the PCI-e x16 slot to 4x or 8x mode? I'd play around with the BIOS settings for the PCI-E slots.
     
  6. StupidDream

    StupidDream n00bie

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    Well like I say with a new processor it works just fine exactly like I would expect it to but the new processor has 20 lanes available where as the old one was limited to 16
     
  7. elite.mafia

    elite.mafia Broke Back [H]

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    I mean I ran 4 video cards off an amd sempron. You don't need to use all 16 lanes for one card. Should be able to just use the x16 slot in a lower mode. But if ur trying to game I could see why you might not want that.
     
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  8. cybereality

    cybereality 2[H]4U

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    Try enabling "Above 4G Decoding" in BIOS. Usually that is needed if you have many video cards (i.e. for mining).
     
  9. StupidDream

    StupidDream n00bie

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    Thanks I’ll look at that. This on is a little more complex since I want to game as well as mining with more than one card

    My other rig was easy. 4x rx580 all on risers
     
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  10. DigitalGriffin

    DigitalGriffin [H]ardness Supreme

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    Sometimes motherboards have a limited number of PCIe lanes. They may have multiple PCIe slots, but you have to go into the BIOS and tell it you are using those slots. Unfortunately this will lower the number of lanes each PCIe slot has. This is why they don't always enable them by default.
     
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  11. thebufenator

    thebufenator Gawd

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