6700k PCie lanes

[LeviBW]

I am planning to build a gaming pc in the coming weeks using a i7-6700k. I am a little worried about the number of PCIe lanes that i have available. I am going to have 2 gtx 1070 in SLI, 2 mechanical hard drives and an m.2 PCIe ssd. I know that each GPU will run at 8x and that the m.2 ssd uses 4 PCIe lanes. Won't that max out the lanes so i cant have any sata drives or will it only disable some of the sata ports? Should i go for a SATA ssd instead of an M.2 one? 

[digitaldoughnut]

The hard drives shouldn't affect the pcie lanes

[TheRandomness]

2 minutes ago, digitaldoughnut said:

The hard drives don't affect the pcie lanes

ftfy

@LeviBW Your CPU will handle the graphics card's PCIe lanes, and the chipset will handle the NVMe M.2 drive. You're fine. 

[stealth80]

the m.2 will use pci lanes from the chipset, the gpus from the CPU so will be fine 

[Sakkura]

11 minutes ago, LeviBW said:

I am planning to build a gaming pc in the coming weeks using a i7-6700k. I am a little worried about the number of PCIe lanes that i have available. I am going to have 2 gtx 1070 in SLI, 2 mechanical hard drives and an m.2 PCIe ssd. I know that each GPU will run at 8x and that the m.2 ssd uses 4 PCIe lanes. Won't that max out the lanes so i cant have any sata drives or will it only disable some of the sata ports? Should i go for a SATA ssd instead of an M.2 one? 

The two 1070s will share the 16 PCIe 3.0 lanes directly from the CPU, 8 each - which is plenty.

 

The M.2 PCIe SSD will take 4 PCIe 3.0 lanes from the chipset, separately from the CPU lanes. The chipset can provide up to 20 of them. The HDDs will each occupy one HSIO port, of which there are 28 available in total. So you're a heck of a long way from running out of PCIe lanes or HSIO ports on the chipset.

[LeviBW]

6 minutes ago, TheRandomness said:

ftfy

@LeviBW Your CPU will handle the graphics card's PCIe lanes, and the chipset will handle the NVMe M.2 drive. You're fine. 

@TheRandomness @stealth80

But doesnt  the SATA interface also use PCIe lanes from the chipset, so the M.2 ssd will use all 4 of the chipset's PCIe lanes and there will be no more for the sata drives?

[TheRandomness]

3 minutes ago, LeviBW said:

@TheRandomness @stealth80

But doesnt  the SATA interface also use PCIe lanes from the chipset, so the M.2 ssd will use all 4 of the chipset's PCIe lanes and there will be no more for the sata drives?

The chipset has 20 lanes, not 4. 

[LeviBW]

1 minute ago, Sakkura said:

The two 1070s will share the 16 PCIe 3.0 lanes directly from the CPU, 8 each - which is plenty.

 

The M.2 PCIe SSD will take 4 PCIe 3.0 lanes from the chipset, separately from the CPU lanes. The chipset can provide up to 20 of them. The HDDs will each occupy one HSIO port, of which there are 28 available in total. So you're a heck of a long way from running out of PCIe lanes or HSIO ports on the chipset.

Oh I see, so its 16 lanes on the CPU and 20 on the chipset for 36 in total. I thought it was 16 on the cpu 4 on the chipset for 20 in total. If i add more PCIe expansion cards in the future (capture card, wifi card, ect.) since all 16 of the CPU lanes are being used will those devices use the lanes of the Chipset?

 

[Sakkura]

29 minutes ago, LeviBW said:

Oh I see, so its 16 lanes on the CPU and 20 on the chipset for 36 in total. I thought it was 16 on the cpu 4 on the chipset for 20 in total. If i add more PCIe expansion cards in the future (capture card, wifi card, ect.) since all 16 of the CPU lanes are being used will those devices use the lanes of the Chipset?

 

Yes.

 

There is one detail though, the bandwidth between the chipset and the CPU is somewhat limited, so you can't realistically put multiple fast M.2 SSDs there and expect them to all run at full speed simultaneously (even if there are plenty of PCIe lanes). But with a single SSD it's not really an issue at this point.

[Ensho]

49 minutes ago, LeviBW said:

@TheRandomness @stealth80

But doesnt  the SATA interface also use PCIe lanes from the chipset, so the M.2 ssd will use all 4 of the chipset's PCIe lanes and there will be no more for the sata drives?

Depends on which M.2 slot you use.  My mobo (Gigabyte Z170X Gaming 7) has two, and as long as I use the lower one beneath the GPU, I have access to all my SATA ports.  If I use the top one, then I lose 4 of my SATA ports.  The bottom M.2 slot, which is the preferred one, shares bandwidth with the bottom x4  PCIe slot, so that PCIe slot is deactivated..and not the SATA ports as mentioned when an NVMe drive is installed in it.  I'd rather have access to my all the SATA ports on the board and only lose the lower PCIe slot which I have no need for anyway...although I could technically use a PCIe adapter for my 960 and put it in the lower slot if I needed to get temps down (which it appears I don't)...but the lower M.2 slot would not work (which would make no difference anyway in that scenario).

 

So, bottom line is, if the mobo you are looking to get only has one M.2 slot, then you probably don't have anything to be concerned about.  If the mobo you are looking to get has two M.2 slots, then look at the owners manual and look to see how the lanes are configured.  More than likely you will need to install it in the lower slot.