How to enable 2nd M.2 slot to run at x4 not x1

[trav.simpson]

I have an ASUS ROG Strix z370-i I have to 1TB Samsung Pro 970's in both slot 1 and slot 2. I have a 1080GTX in the standard PCIe 16x slot.

Current Specs:
Intel 8700k @ 3.7ghz
Asus Rog Strix z370
2x Samsung Pro 970 1TB
windows 10 Professional in (BIOS Mode UEFI)
NZXT 200i Case
CORSAIR HXi Series, HX1000
Corsair LPX 32GB (2x16GB) 3200MHz C16 DDR4

After testing and downloading the Samsung Magic app I found one of my slots is only running at x1 (where the current installed OS is). I have nothing plugged into any SATA port (so it's obviously not lowering its speed due to a shared drive), and I've gone into the BIOS and completely disabled all SATA drives.

Here is an image from the Samsung Magic app comparing the two drives:

 

[velocityg4]

Unfortunately their manual is poorly documented. I'd say go into the BIOS and the Advanced menu.

One possible option is to enable Hyper M.2X16 in Onboard Devices Configuration. I'd also look at the options under PCH.

 

[kanewolf]

I don't believe you can change that slot. It is hard wired with only a single PCIe lane. That is a limitation of the motherboard hardware.

 

[psoohoo]

the website suggests its 2 m.2 pcie-x4 slots. can i assume you have no other devices connected?
Does the BIOS have any means of identifying whether its a x1 or x4?

 

[trav.simpson]

Correct nothing else connected.

 

[trav.simpson]

I'm still unable to solve this problem, I've even contacted ASUS who says both ports should be defaulting to x4 if there the SATA connection is not being used.

 

[trav.simpson]

I fixed the issue.

Strangely, my OS drive was installed on the M.2 drive on the back of the motherboard, while my secondary drive was installed in front, where all of the other mobo controls are. However, once I swapped the drives everything was fixed. The OS drive should be on the "top" most socket while a secondary drive can be installed on the reverse side of the motherboard and still run at x4 speed.

 

[JoshADA2828]

I fixed the issue.

Strangely, my OS drive was installed on the M.2 drive on the back of the motherboard, while my secondary drive was installed in front, where all of the other mobo controls are. However, once I swapped the drives everything was fixed. The OS drive should be on the "top" most socket while a secondary drive can be installed on the reverse side of the motherboard and still run at x4 speed.

I’m having an issue regarding my vga drivers not loading after enabling hyperm.2x16 In my bios on my z-370-e because that’s the only way I could get the system to recognize I installed a fresh 970 evo nvme into my second m.2 port. Now my only issue seems to be my system booting out of whack. My second m.2 port is actually my “top” port, should I swap my m.2’s and see if that works? My other m.2 is sata though so I’m not sure if that will be an issue but I’m not sure what else I could do

 

[USAFRet]

I’m having an issue regarding my vga drivers not loading after enabling hyperm.2x16 In my bios on my z-370-e because that’s the only way I could get the system to recognize I installed a fresh 970 evo nvme into my second m.2 port. Now my only issue seems to be my system booting out of whack. My second m.2 port is actually my “top” port, should I swap my m.2’s and see if that works? My other m.2 is sata though so I’m not sure if that will be an issue but I’m not sure what else I could do

Please start a new thread for your particular situation.
This one is coming up on 3 years old.