Does installing M.2/nvme drive on Asus x99a ii mobo with i6800K CPU disables certain pcie slots?

[pcHobby]

I am thinking of buying a 10gbe or thunderbolt 3 pcie card but I recall reading a while back that installing an M.2 or Nvme drive will disable the 2 bottom Pcie slots due to limited channels or something with the i6800k cpu?

I already have the other pcie slots filled with a 2 slot GPU and network card.

Can someone clarify this, as I do not want to buy a pcie card that I do not have the available working slot to use.

Thank you.

 

[N3rdR4ge]

the manual does not say anything about slots being disabled from m.2 use. as far as i know, most motherboards will just share the pcie lanes with the m.2 slot, not disable a lane entirely.

manual:
http://dlcdnet.asus.com/pub/ASUS/mb/LGA2011/X99-A_II/E11090_X99-A_II_UM_WEB.pdf?_ga=2.126226573.1874514352.1530289124-309142270.1530289124

 

[jay32267]

I too am under the impression that the PCIe lanes are shared....although I would like to know HOW they are shared when you go over the total amount.

 

[Rogue Leader]

The i7-6800k has 28 PCIe lanes. 4 of those are dedicated to the M.2 slot on that motherboard. The Chipset has 8 PCIe lanes which are dedicated to slots 2, 3, and 5 (2 and 5 are x1 slots, 3 is a 2.0 x16 slot). The other 3 slots are x16, x16/x8 or x8x8x8, you will note that adds to 24, leaving the other 4 lanes for the M.2 slot.

 

[pcHobby]

The i7-6800k has 28 PCIe lanes. 4 of those are dedicated to the M.2 slot on that motherboard. The Chipset has 8 PCIe lanes which are dedicated to slots 2, 3, and 5 (2 and 5 are x1 slots, 3 is a 2.0 x16 slot). The other 3 slots are x16, x16/x8 or x8x8x8, you will note that adds to 24, leaving the other 4 lanes for the M.2 slot.

I am confused to how this works. So it has 28 lanes for pcie;
slot 2, 3, 5 = 8 lanes
slots 1, 3, 6 = 16 lanes??
m.2 = 4 lanes
Total = 28 lanes

Maybe it is the SATA drives that causes some of the pcie lanes not to work properly?
If I fill up all the sata drive ports with drives, add m.2 or nvme drive, and use all the pcie slots with graphic cards, etc., will for example pcie slot 6 or slot 4 or both, work with a asus thunderboltex 3 card or qnap 10gbe network card properly where I get the full 10/40gbe speeds?

When you say the lanes becomes shared on the pcie slot, does that mean it will slow down speeds of the thunderboltex 3 card for example or does that mean the card will not function properly?

Thank you.

 

[Rogue Leader]

The i7-6800k has 28 PCIe lanes. 4 of those are dedicated to the M.2 slot on that motherboard. The Chipset has 8 PCIe lanes which are dedicated to slots 2, 3, and 5 (2 and 5 are x1 slots, 3 is a 2.0 x16 slot). The other 3 slots are x16, x16/x8 or x8x8x8, you will note that adds to 24, leaving the other 4 lanes for the M.2 slot.

I am confused to how this works. So it has 28 lanes for pcie;
slot 2, 3, 5 = 8 lanes
slots 1, 3, 6 = 16 lanes??
m.2 = 4 lanes
Total = 28 lanes

Maybe it is the SATA drives that causes some of the pcie lanes not to work properly?
If I fill up all the sata drive ports with drives, add m.2 or nvme drive, and use all the pcie slots with graphic cards, etc., will for example pcie slot 6 or slot 4 or both, work with a asus thunderboltex 3 card or qnap 10gbe network card properly where I get the full 10/40gbe speeds?

When you say the lanes becomes shared on the pcie slot, does that mean it will slow down speeds of the thunderboltex 3 card for example or does that mean the card will not function properly?

Thank you.

Slots 1, 4 and 6 have up to 24 lanes depending on configuration. If you have 1 gpu in slot 1 it runs at x16. if you have 2 GPUs slot 1 runs at x16 and 4 runs at x8. If you have 3 all 3 slots run at x8. The other 4 lanes of the CPU are dedicated to the M.2 slot. Total of 28 lanes - all from the CPU.

The Chipset X99 has 8 PCIe lanes. They are shared by 2 x1 slots (2 and 5) and 1 x16 slot (which runs at a max of x4 - slot 3). This is because these slots share bandwidth with the USB 3.1 ports.

You need to strategically populate your slots. Are you really planning on 4 GPUs and a gigabit card (why? the board has gigabit eithernet) In the end that 4th GPU is going to run at x4 and your thunderbolt or gigabit ethernet card will run at x1. They will work, but at a slower bus speed which will affect the overall speed.

 

[pcHobby]

Thanks for the more detailed explanation!

I was hoping to use the 10gbe as 1gbe is slower. But I am wondering whether I am capable of utilising that with 1 or 2 8tb drives 7200 rpm?

How many NAS drives can the 1gbe connection cope with at raid 0? At what point with drives should a person consider 10gbe connection - for example 3 x 8tb 7200 drives at raid 0?

 

[Rogue Leader]

Thanks for the more detailed explanation!

I was hoping to use the 10gbe as 1gbe is slower. But I am wondering whether I am capable of utilising that with 1 or 2 8tb drives 7200 rpm?

How many NAS drives can the 1gbe connection cope with at raid 0? At what point with drives should a person consider 10gbe connection - for example 3 x 8tb 7200 drives at raid 0?

10GB Qnap cards like that are for WAY more than you could ever imagine to put through as a single person. Those cards are used in servers with hundreds of people accessing them at the same time. Your bottleneck is the 7200rpm hard drives, not the 1gb connection.

There really is no relation between the number of hard drives you are running in RAID and the speed of the connection you need. Aside from the fact you are talking about 2 different systems here. These drives will be in a seperate NAS with a 10gb connector on it? Do you have the rest of the hardware you'd need to run that? Aside from the fact its a massive overkill waste of money for one or even 10 people.