Will I have enough lanes?

Hi all,
I was looking at adding a M.2 PCI-E card into my desktop in the x4 PCI-E slot so that I could run raid 0 with some NVME drives however Im not sure if my cpu (i7 4790)will have enough lanes due to the amount of other peripherals that are in the system. They are the following:
2x GTX 980 SLI
Creative sound blaster sound card (1x slot)
Gigabyte Z97X-UD5H-BK rev 1

will adding this card result in one of the GPU’s dropping from SLI due to not having enough lanes?

I know that the i7 only has 16 lanes and that means that there must be some card in the system not running at its rated speed or the motherboard has a PLX chip in it however im not sure how to see that.

What model motherboard are you using? Your link just goes to the Gigabyte homepage. What other NVMe drives do you have hooked up or want to hook up? How are you planning on implementing the RAID0 (Windows dynamic disk or storage spaces, some other software solution)? When we know your motherboard model, we could provide a better answer, but my gut is telling me that this config won’t be possible without stealing lanes from the graphics cards.

You are already running the second 980 at 4x.
Ark says this is PCIe for a 4790: Up to 1x16, 2x8, 1x8+2x4

Before we get any further how to deal with this, what is the specific reason to go for NVME or even NVME raid? Because if it is game loading times, you are wasting money.

hmm thats interesting its got the link in the post but it gets changed to the home page, anyway the board is a Gigabyte GA-Z97X-UD5H-BK-rev- 1

currently the rest of the storage media is sata baised and if i were to configure the NVME M.2 I would do it on the motherboards intergrated raid controller and then use that as my C drive.

had one of the drives when i built the system and screwed up the ordering for another system resulting in having one extra so I was looking at using it more as a drive for editing and running some vms off.

If your link has a ‘#’ at the end, just delete it and the link should work. Don’t know why, but that worked for me the last time I linked to Gigabyte’s website.

Anyways, the i7 4790 only has 16 PCIe 3.0 lanes and the Z97 chipset has eight PCIe 2.0 lanes. So you’re already using all 16 PCIe 3.0 lanes and at least one PCIe 2.0 lane. Each PCIe based M.2 drive will use four more PCIe 2.0 lanes from the Z997 chipset, so you really can only use one M.2 drive if using the soundcard.

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Cool, I guess that I will save the drive for another system. thanks for the help everyone!

According to the motherboard specifications, the x4 slot shares bandwidth with the two x16 slots.

  • If you only have one device, using the top x16 slot will have it running @x16.
  • If you have two devices, the two x16 slots will both run @x8.
  • If you have three devices, the top x16 slot will run @x8, the second and the third slot will both run @x4.

Conclusion: SLI requires x8 per device, so will not be available if you use the x4 slot on this motherboard.

EDIT: Another point to make would be that if you were to connect a second M.2 drive thru the [email protected] expansion slot, that drive would be connected directly to the CPU. This would mean that you could not use RAID on it. (Windows volume is another matter, but you can’t boot off that.)

EDIT2: Yet another point: The M.2 slot (on Z97) runs thru the PCH, will always be PCIe 2.x and usually just x2. This means it has a lot less bandwidth than a drive connected to an expansion slot (~1 MB/s versus ~4 MB/s). So combining them would probably not be a good idea even if you could do it - you’d get more performance from your secondary drive by running it separately.


You really don’t want to raid 0 nvme’s - there’s no real life performance benefits and you’re just making your system more prone to failure.
Just use it as a secondary drive.

Derp, I completely forgot OP wanted to run it through an x4 slot.

Definitely not gonna work then.

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