Question How to install three Nvme SSDs on Asus Prime 7390-A? Very confused

[bionucular]

Hello everyone, this is my first question here. 😊 I want to expand my PC storage (and its speed) for audio production and I need 2 additional SSD Nvme drives for data and samples (2TB x 2). I already have 1 Nvme with the OS (and a HDD, which I'd disconnect and use as external backup).

So, my motherboard is ASUS Prime Z390-A, CPU is Intel i5-9600K and in the mobo manual, the relevant storage options are:

• 1 x M.2_1 Socket (SATA & PCIe mode) - occupied
• 1 x M.2_2 Socket (PCIe x4 mode) - free
• -PCIe X16_1 slot supports up to 3 Intel PCIe NVME SSDs via a Hyper M.2 X16 card -occupied by GPU
• PCIe X16_2 slot supports up to 2 Intel PCIe NVME SSDs via a Hyper M.2 X16 card - free

Upon researching the Hyper M.2 card, available PCIe lanes, bifurcation etc. I'm just becoming more confused. While the manual suggest the Hyper card as the only way to utilize PCI-e slots for storage (and also requries Intel drives?), some people recommend to avoid it because it's meant for RAID arrays or because it requries a free x16 slot with full bandwith. And I don't have that much because according to Intel, my CPU has 16 available lanes, and I don't know how many the GPU uses.

So my question is, what's the optimal way to run 3 NVMe SSDs on this motherboard without r/w speed throttling? My guess is, fill in the remaining M.2_2 slot so I have 2 SSDs in intended positions (bypassing PCI-e) and somehow add the 3rd one via a PCI-e adapter card? Because putting both new SSDs in the PCIe expansion slot doesn't sound right. I attached the mobo diagram, and the confusing bifurcation info. Thanks for your help!

 

[Fix_that_Glitch]

Why not just use a 4tb ssd?

 

[SkyNetRising]

So my question is, what's the optimal way to run 3 NVMe SSDs on this motherboard without r/w speed throttling?
My guess is, fill in the remaining M.2_2 slot so I have 2 SSDs in intended positions (bypassing PCI-e) and somehow add the 3rd one via a PCI-e adapter card?

Use two M.2 slots on motherboard.
Add third M.2 drive on PCIE M.2 adapter (adapter for single M.2 drive).
Place it in PCIE_x16_3. Switch PCIE_x16_3 operation mode to x4 in BIOS (this disables sata ports SATA5, SATA6).

 

[Bob.B]

Hello everyone, this is my first question here. 😊 I want to expand my PC storage (and its speed) for audio production and I need 2 additional SSD Nvme drives for data and samples (2TB x 2). I already have 1 Nvme with the OS (and a HDD, which I'd disconnect and use as external backup).

So, my motherboard is ASUS Prime Z390-A, CPU is Intel i5-9600K and in the mobo manual, the relevant storage options are:

• 1 x M.2_1 Socket (SATA & PCIe mode) - occupied
• 1 x M.2_2 Socket (PCIe x4 mode) - free
• -PCIe X16_1 slot supports up to 3 Intel PCIe NVME SSDs via a Hyper M.2 X16 card -occupied by GPU
• PCIe X16_2 slot supports up to 2 Intel PCIe NVME SSDs via a Hyper M.2 X16 card - free

Upon researching the Hyper M.2 card, available PCIe lanes, bifurcation etc. I'm just becoming more confused. While the manual suggest the Hyper card as the only way to utilize PCI-e slots for storage (and also requries Intel drives?), some people recommend to avoid it because it's meant for RAID arrays or because it requries a free x16 slot with full bandwith. And I don't have that much because according to Intel, my CPU has 16 available lanes, and I don't know how many the GPU uses.

So my question is, what's the optimal way to run 3 NVMe SSDs on this motherboard without r/w speed throttling? My guess is, fill in the remaining M.2_2 slot so I have 2 SSDs in intended positions (bypassing PCI-e) and somehow add the 3rd one via a PCI-e adapter card? Because putting both new SSDs in the PCIe expansion slot doesn't sound right. I attached the mobo diagram, and the confusing bifurcation info. Thanks for your help!

Consider one m.2 in the free slot and one 2.5 sata ssd.

 

[bionucular]

Why not just use a 4tb ssd?

Thanks everyone for very useful responses! I suppose that a single 4TB SSD would normally be the best idea, but I don't want to have my projects and sample libs on the same drive. I would really like to separate those storages with completely different read/write cycles. If not for performance and durability, then to avoid the fear of losing everything if it fails. Besides, I already have the samples on a separate drive and it would be a pain to change all file paths.

I was mostly thinking about what Bob said, a sata ssd for projects and software is just fine. But SkyNet's response kinda reminded me about what I've glanced over in the manual, but forgot to mention in my post:
The PCIe x16_3 slot (max at x4 mode) shares bandwith with SATA_5 and SATA_6. The PCIe x16_3 is default set at x2 mode.

This aligns exactly with what SkyNet said:

Use two M.2 slots on motherboard.
Add third M.2 drive on PCIE M.2 adapter (adapter for single M.2 drive).
Place it in PCIE_x16_3. Switch PCIE_x16_3 operation mode to x4 in BIOS (this disables sata ports SATA5, SATA6).

So by disabling sata 5 and 6, I'd get another x2 bandwith and end up with a normal x4 connection that should fully utilize nvme ssd speeds. It's slightly more expensive than a sata solution, but without speed throttling it's worth it . So I'll think about it and let you know!

 

[bionucular]

Hello everyone, here's the update! The installation went fine apart from some hiccups, and both drives work normally. However, one of them is surprisingly slower. The drive in the PCIe_3 slot, after enabling x4 bandwith and disabling sata 5 &6, runs at full speed, 3500 mb/s read. The other drive, in the designated empty M.2 slot, runs with only 800-900 mb/s as if it shares bandwith with something.

This is not entirely bad nor do I need it to be as fast as the other one, it's just strange to me. It could be that it shares bandwith with the existing system Nvme and the benchmarking tool somehow uses both.

 

[SkyNetRising]

The other drive, in the designated empty M.2 slot, runs with only 800-900 mb/s as if it shares bandwith with something.

What model M.2 drives? Are they all the same?

 

[bionucular]

Yeah, the 2 new drives are the same, Samsung 970 EVO+ so it must be about the ports. The existing SSD, in M.2_1 slot, is an ADATA XPG with the same speed rating. I disabled all sata ports (except the first one because then I couldn't even boot). Maybe it's about the benchmarking program, Crystal Disk using specific scenarios. I mean, 800 mb/s is still fast, and I don't need both drives to be the same speed, but I'm just curios

 

[bionucular]

One additional update: After exploring the BIOS/UEFI options, and comparing them with the manual and other people's screenshots, it seems that M.2 bandwith settings are simply missing. Under Advanced > Onboard Devices Config there should be two M.2 settings for each slot (like SATA/x2/x4 mode. Also, NVMe Configuration is greyed out (under NVMe config and drive information). I've even updated the UEFI to the latest version, nothing changed. I contacted ASUS support so we'll see.