Question PCIe slot for storage expansion

[jhansman]

So I have a free PCIe (2.0 x 16) slot in my mobo that I think I can use with a SIIG PCIe adapter I bought some time ago that will take an NVMe drive. According to the info on SIIG's site, this adapter can only be used with an NVMe drive (M key), and is not compatible with B key drives (SIIG adapter). Question is, is there any point in using such a drive in such a slot, or will it be retarded by the speed of the lane? I'm out of SATA connectors and this is the only way I can add internal storage to my current setup. Thanks for any help you all can lend.

 

[Micrornd]

Any difference in speed between an (good) M.2 adapter with a NVMe drive and a NVMe drive in a dedicated M.2 slot will be very minimal and only show up in benchmarks.

You could always add a SATA card in a pci-E slot
Since you mentioned the SIIG line - https://www.siig.com/it-products/controllers-storage/serialata/pcie.html

 

[jhansman]

Any difference in speed between an (good) M.2 adapter with a NVMe drive and a NVMe drive in a dedicated M.2 slot will be very minimal and only show up in benchmarks.

You could always add a SATA card in a pci-E slot
Since you mentioned the SIIG line - https://www.siig.com/it-products/controllers-storage/serialata/pcie.html

Yeah, I could, but I'd really rather just keep it all internal. Good to know about the speed difference (or lack thereof) with the adapter. I will keep an eye out for deals on an NVMe drive and pick one up. Thanks.

 

[Insert_Nickname]

You could always add a SATA card in a pci-E slot

You can get add-in PCIe cards which allow you to add four SATA drives to a single PCIe slot:

f.x.
https://www.delock.com/produkte/1140_M-2/89588/merkmale.html

Essentially an add-in M.2 SATA RAID controller with four ports. I'm sure something comparable is available in the US.

 

[Micrornd]

but I'd really rather just keep it all internal

Yes, the page I linked shows internal SATA ports, just scroll down

 

[jhansman]

I'm afraid I failed to make my desires clear, so let me try again: My goal here is to add another NVMe drive to my system using the SIIG adapter. I have enough (three, to be exact) SATA3 drives as it is, so if this slot, described as "1 x PCI Express 2.0 x16 Slot (PCIE3: x4 mode)" in the manual, would give me more throughput than a SATA3 drive, it might be worth it to pick up an affordable NVMe drive and use the slot. I realize that this setup would not be as quick as the M.2 NVMe drive I boot from (which is crazy fast), but if it's speedier than SATA3, well, why not? So again, thanks for any info you all can provide.

 

[Insert_Nickname]

My goal here is to add another NVMe drive to my system using the SIIG adapter.

Shouldn't be any issue. The drive will just drop from PCIe 3.0 x4 to PCIe 2.0 x4. Depending on which drive you select, you'll loose a bit of sequential troughput. PCIe 2.0 x4 is limited to in practice about 1600MB/s both ways. Random R/W shouldn't be affected much, if at all.

Depending on what platform you're on, be aware the pre-Skylake Intel CPUs use DMI 2.0. Which can be completely saturated by modern high performance NVMe drives, if the slot is connected to the PCH. It should be detailed in your mainboard manual if the slot is thus connected.

 

[Steltek]

You can get add-in PCIe cards which allow you to add four SATA drives to a single PCIe slot:

f.x.
https://www.delock.com/produkte/1140_M-2/89588/merkmale.html

Essentially an add-in M.2 SATA RAID controller with four ports. I'm sure something comparable is available in the US.

I think you have to be sure you have a motherboard that supports PCIe lane bifurcation in order to be able to see more than one drive with these cards. AMD-based boards (most especially the relatively newer ones) seem to have few problems with these cards, but many Intel chipset boards won't work properly with them (all you can see is one of the four installed cards on them). And some Intel systems can similarly have problems setting up RAID arrays with these cards.

 

[Insert_Nickname]

I think you have to be sure you have a motherboard that supports PCIe lane bifurcation in order to be able to see more than one drive with these cards.

That is completely correct, if you're using PCIe NVMe M.2 drives. Then you'll want something like this one:

https://www.delock.com/produkte/1140_M-2/89835/merkmale.html

That particular card however uses a Marvell 9235 PCIe-to-SATA controller. It's a SATA-M.2-RAID-on-a-PCIe-card. You'll only get SATA speeds out of it, but it does make for some interesting possibilities. RAID-5/10 on a single expansion card f.x.

 

[jhansman]

Shouldn't be any issue. The drive will just drop from PCIe 3.0 x4 to PCIe 2.0 x4. Depending on which drive you select, you'll loose a bit of sequential troughput. PCIe 2.0 x4 is limited to in practice about 1600MB/s both ways. Random R/W shouldn't be affected much, if at all.

Depending on what platform you're on, be aware the pre-Skylake Intel CPUs use DMI 2.0. Which can be completely saturated by modern high performance NVMe drives, if the slot is connected to the PCH. It should be detailed in your mainboard manual if the slot is thus connected.

As shown in my sig, I'm running a Ryzen 5 3600, so I reckon that concern is null. Good to know about the throughput of the slot. I figured this setup would not give me the performance I'm getting from the Sammy 970 Pro I have in the PCIe 3.0 M.2 slot I boot from, but even so it would be nice to have more 21st century storage inside. I think this will just have to be one of those "try it and see what happens" deals. I failed to mention that this slot is right up against my vid card and would likely block at least some fan exhaust, so it may all be academic. If I knew half of what I've learned since I did this build, I would probably have gotten a different motherboard that would have offered more room and options. Live and learn....

 

[Insert_Nickname]

I failed to mention that this slot is right up against my vid card and would likely block at least some fan exhaust, so it may all be academic.

Having looked at your mainboard and graphics card layout, I think you mean fan intake. I'd try first, see how things work. There are low profile PCIe adaptors available if airflow becomes an issue.

f.x.
https://www.silverstonetek.com/product.php?pid=814&bno=116&tb=51&area=en

 

[jhansman]

Good to know, thanks! And yeah, intake.