[SOLVED] Nvme adapter on second PCIE x16 slot

komando626

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May 2, 2016
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Hi guys,

My Nvme slot is broken for some reason, so I'm planning to buy nvme to pcie adapter and plug it on the second pcie 3.0 x16 slot. is the nvme to pcie adapter will slow my GPU or will it make the GPU run x8? other than the Nvme as boot drive, I'm currently using 1 sata SSD and 1 HDD
my motherboard has 4 slot of Pcie 2.0 x1 and 2 slot of Pcie 3.0 x16
my pc spec:
Mobo: Asrock X370 K4
Proc: Ryzen 5 1600
Ram: gskill ripjaws V 16GB
bootdrive: Adata 8200 256GB
SSD: Samsung 860 evo 500gb
HDD: Seagate barracuda 3TB


thanks!
 
Solution
NVMe is connected by PCIe lanes straight from CPU, it can make use of up to 4 lanes which is normal for it. So does PCIe x16 slot(s) and all depends on umber of PCIe lanes from CPU.
Ryzen 1600(x) has in total 20 PCIe lanes,
Ryzen 3600(x) has 24 PCIe lanes, that's where discrepancy between PCIe usage lies. Some have more, some less.
Ryzen 1000 and 2000 series have 20 and 3000 and 5000 series 24.
I believe, precisely, all Ryzen CPU's have 24 PCIe lanes, with 20 lanes available for use with NVME (4) and GPU (16) (APU's keep 8 GPU lanes for the iGPU). There are 4 lanes dedicated to communicating with the chipset, can't be re-allocated and are largely ignored so that could the the source of the disparity.

Any other lanes come from...
Hi guys,

My Nvme slot is broken for some reason, so I'm planning to buy nvme to pcie adapter and plug it on the second pcie 3.0 x16 slot. is the nvme to pcie adapter will slow my GPU or will it make the GPU run x8? other than the Nvme as boot drive, I'm currently using 1 sata SSD and 1 HDD
my motherboard has 4 slot of Pcie 2.0 x1 and 2 slot of Pcie 3.0 x16
my pc spec:
Mobo: Asrock X370 K4
Proc: Ryzen 5 1600
Ram: gskill ripjaws V 16GB
bootdrive: Adata 8200 256GB
SSD: Samsung 860 evo 500gb
HDD: Seagate barracuda 3TB


thanks!
https://www.asrock.com/mb/AMD/Fatal1ty X370 Gaming K4/index.asp#Specification
2 x PCI Express 3.0 x16 Slots (single at x16 (PCIE2); dual at x8 (PCIE2) / x8 (PCIE4))*
So PCIe lines are shared in PCIe x16 slots. Both are from CPU. Using second x16 slot will make both run at x8. Depending on GPU, that may not cut it's performance much or at all.
 
https://www.asrock.com/mb/AMD/Fatal1ty X370 Gaming K4/index.asp#Specification
2 x PCI Express 3.0 x16 Slots (single at x16 (PCIE2); dual at x8 (PCIE2) / x8 (PCIE4))*
So PCIe lines are shared in PCIe x16 slots. Both are from CPU. Using second x16 slot will make both run at x8. Depending on GPU, that may not cut it's performance much or at all.
hey thx for the response!
let's assumed my nvme slot working just fine and i use the nvme slot. is that mean the GPU running on x16 lane or x8 lane? because I could not find any explanation from the manual about what lane the nvme slot using
 
hey thx for the response!
let's assumed my nvme slot working just fine and i use the nvme slot. is that mean the GPU running on x16 lane or x8 lane? because I could not find any explanation from the manual about what lane the nvme slot using
NVMe is connected by PCIe lanes straight from CPU, it can make use of up to 4 lanes which is normal for it. So does PCIe x16 slot(s) and all depends on umber of PCIe lanes from CPU.
Ryzen 1600(x) has in total 20 PCIe lanes,
Ryzen 3600(x) has 24 PCIe lanes, that's where discrepancy between PCIe usage lies. Some have more, some less.
Ryzen 1000 and 2000 series have 20 and 3000 and 5000 series 24.
 
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NVMe is connected by PCIe lanes straight from CPU, it can make use of up to 4 lanes which is normal for it. So does PCIe x16 slot(s) and all depends on umber of PCIe lanes from CPU.
Ryzen 1600(x) has in total 20 PCIe lanes,
Ryzen 3600(x) has 24 PCIe lanes, that's where discrepancy between PCIe usage lies. Some have more, some less.
Ryzen 1000 and 2000 series have 20 and 3000 and 5000 series 24.
I believe, precisely, all Ryzen CPU's have 24 PCIe lanes, with 20 lanes available for use with NVME (4) and GPU (16) (APU's keep 8 GPU lanes for the iGPU). There are 4 lanes dedicated to communicating with the chipset, can't be re-allocated and are largely ignored so that could the the source of the disparity.

Any other lanes come from the chipset, except that x370 board can allocate 8 of the CPU's 16 lanes intended for the GPU slot to the 2nd PCIe x 16. So in OP's case if he wants PCIe gen 3 NVME in the 2nd x16 slot (up to 2 of them) it would also limit the GPU to 8 lanes from normal 16. For gaming x8 vs. x16 would be unnoticeable performance impact.

However, booting to an NVME on an add-in card is not a simple thing as UEFI doesn't want to do that. In addition it has the potential to leave the system vulnerable to root-kit exploits, so putting the system drive in an adapter is probably not a good idea. BUT... that board also has a 2nd NVME M.2, fed by the chipset so limited to PCIe gen 2 (it might be hidden under the GPU). In practical terms again, gen 2 or gen 3 would be unnoticeable to a user. Since it doesn't appear utilized at this time I'd put the system drive in there, leaving the GPU with full bandwidth and not bother with trying to boot to an NVME in an adapter.
 
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Solution
I believe, precisely, all Ryzen CPU's have 24 PCIe lanes, with 20 lanes available for use with NVME (4) and GPU (16) (APU's keep 8 GPU lanes for the iGPU). There are 4 lanes dedicated to communicating with the chipset, can't be re-allocated and are largely ignored so that could the the source of the disparity.

Any other lanes come from the chipset, except that x370 board can allocate 8 of the CPU's 16 lanes intended for the GPU slot to the 2nd PCIe x 16. So in OP's case if he wants PCIe gen 3 NVME in the 2nd x16 slot (up to 2 of them) it would also limit the GPU to 8 lanes from normal 16. For gaming x8 vs. x16 would be unnoticeable performance impact.

However, booting to an NVME on an add-in card is not a simple thing as UEFI doesn't want to do that. In addition it has the potential to leave the system vulnerable to root-kit exploits, so putting the system drive in an adapter is probably not a good idea. BUT... that board also has a 2nd NVME M.2, fed by the chipset so limited to PCIe gen 2 (it might be hidden under the GPU). In practical terms again, gen 2 or gen 3 would be unnoticeable to a user. Since it doesn't appear utilized at this time I'd put the system drive in there, leaving the GPU with full bandwidth and not bother with trying to boot to an NVME in an adapter.
currently I'm using the 2nd M.2 slot, but the 2nd slot is SATA so my Nvme speed is limited. is there some way to make the 2nd slot work as Nvme?
 
currently I'm using the 2nd M.2 slot, but the 2nd slot is SATA so my Nvme speed is limited. is there some way to make the 2nd slot work as Nvme?
According to the board's spec sheet:
- 1 x M.2 Socket (M2_2), supports M Key type 2230/2242/2260/2280 M.2 SATA3 6.0 Gb/s module and M.2 PCI Express module up to Gen2 x2 (10 Gb/s)
https://www.asrock.com/mb/AMD/Fatal1ty X370 Gaming K4/index.asp#Specification

That tells me you take out the M.2 SSD and put your M.2 NVME, also called a PCI Express module, in the 2nd M.2 socket. The controller (in the chipset) negotiates the highest transfer protocol supported by both and then just works. If the NVME has the system on it then BIOS should find the EFI partition there and boot from it. You may have to use another computer to recover the data from the M.2 SSD.
 
According to the board's spec sheet:
- 1 x M.2 Socket (M2_2), supports M Key type 2230/2242/2260/2280 M.2 SATA3 6.0 Gb/s module and M.2 PCI Express module up to Gen2 x2 (10 Gb/s)
https://www.asrock.com/mb/AMD/Fatal1ty X370 Gaming K4/index.asp#Specification

That tells me you take out the M.2 SSD and put your M.2 NVME, also called a PCI Express module, in the 2nd M.2 socket. The controller (in the chipset) negotiates the highest transfer protocol supported by both and then just works. If the NVME has the system on it then BIOS should find the EFI partition there and boot from it. You may have to use another computer to recover the data from the M.2 SSD.
yes, I use adapter for my Samsung 860 M.2 then plug it to the SATA port and then put my Nvme on the 2nd M.2 socket, but the speed is only limited at Read 880MB/s and 700ish MB/s Write. and yes my Nvme has windows 10 in it, but what I didn't understand is why my speed is limited as I say above, I believe 1 GByte/s is the least Read speed I can achieve if the port support up to 10 Gbit/s. is there any setting need to be done in the bios first?
 
yes, I use adapter for my Samsung 860 M.2 then plug it to the SATA port and then put my Nvme on the 2nd M.2 socket, but the speed is only limited at Read 880MB/s and 700ish MB/s Write. and yes my Nvme has windows 10 in it, but what I didn't understand is why my speed is limited as I say above, I believe 1 GByte/s is the least Read speed I can achieve if the port support up to 10 Gbit/s. is there any setting need to be done in the bios first?
The 2nd M.2 NVME will be PCIe gen 2 bandwidth; the 1st M.2 was PCIe gen 3. Gen 2 is still very, very fast, a lot faster than SATA. You're not likely to ever notice a difference since the way Windows works is with frequent small, random reads from scattered files. The only way to appreciate the extreme high transfer speed of NVME's is with sequential reads of very large files, something more typical of data servers.

You may have to change a BIOS setting for which drives to look on for the system partition. I'd first just put the system NVME in the 2nd M.2 and see if it works as most BIOS' look on all attached drives by default.
 
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