Dual M2 PCI-E Card

Soldato
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I've looked at the various card readily available and I'm still at a bit of a loss as to whether they'll do what I want....

I'm after a PCI-E card to host 2x m2 SSDs.

These can be either SATA or NVME, speed isn't too much of a concern, but it would be nice if I could drop in any type of m2 SSD for flexibility.

I'd like to be able to retain ALL my motherboard's SATA connections and run solely from the PCI-E slot and have both drives as seperate disks.

What I don't want is anything that requires a SATA cable connected to the motherboard and uses the motherboard's SATA controller, only operates in RAID or is only compatible with a certain motherboard or CPU combo.

The closest I've found is the ASUS HYPER M.2 PCIe x16 NVMe VROC RAID Card V2

Does this do what I'm after, but give me up to 4 disks?

Any advice appreciated. Thanks.
 
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What drive(s) did you plan on getting? The Asus card is PCIe 3.0 x16 instead of PCIe 4.0.

One thing worth menitoning and a HUGE downside to m2 PCIe cards, is that they suck up bandwith from the GPU x16 lane. When I used one, the bandwith on my 2080 Ti went through the floor and I ended up losing 20-50fps in some games!
Fast at data read/write but nothing will beat a motherboard that has on board M2 slots.

This is one of my reasons I updated to an X570 board
 
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NVME drives are a bit of a pain as, due to their architecture, they require 4 PCI lanes - there’s no getting around it. This is why you can lose some sata drive ports if you use the second M2 slot on a motherboard - the top one connects straight to the CPU, which is great for the OS and games, but everything else will go through the chipset and be limited by those speeds.

Example: the Ryzen B450 boards have 24 lanes to the CPU. 4 go to the chipset, 4 go to the M2 top slot, and 16 go to the PCI expansion slots. So, if you have a GPU and an M2 drive fitted, that’s all the lanes taken. If you want to use another of the long 16x slots, the top one with your GPU will be changed to and 8x, with the other 8 lanes to whatever you have in the second expansion slot. Some motherboards allow more splitting of these lanes, known as birfurcation, so you can specify what slot has what number of lanes - it’s worth mentioning that even high end GOU’s struggle to max out an 8x pci 3.0 lane, so having something else in the second slot doesn’t usually effect performance.

So, if you want more NVME drives, you need an expansion card and you need 4 lanes per drive. The ASUS card, and any card which has 4 slots on it, would need 16 lanes to itself to address all 4 drives, so you’d have to forego a GPU or get a thread ripper (many, many lanes...) At best you can run your GPU at 8x and have 2 drives on the ASUS card using the other 8x lanes.

the big question is if you need the speeds for anything other than the OS and games. You can buy PCI cards from Sedna which can have 4 sata drives on them and would be probably quick enough for data storage without having all the cables around. The other option is to get a card with a switch on it so it can access each drive independantly, it these are stupidly expensive...
 
Soldato
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NVME drives are a bit of a pain as, due to their architecture, they require 4 PCI lanes - there’s no getting around it. This is why you can lose some sata drive ports if you use the second M2 slot on a motherboard - the top one connects straight to the CPU, which is great for the OS and games, but everything else will go through the chipset and be limited by those speeds.

They are not a pain, you just need to have a compatible motherboard. @jellybeard999 What motherboard do you have?

In my MB manual it says

M2_1~3: M.2 Slots (Key M)
The following table describes the relationship between the M.2 slots and the PCIe bandwidth of the processors

Slots 3rd Gen AMD Ryzen™ 2nd Gen AMD Ryzen™
M2_1 (CPU) PCIe 4.0 x4 PCIe 3.0 x4
M2_2 (PCH) PCIe 4.0 x4 PCIe 3.0 x4
M2_3 (PCH) PCIe 4.0 x4 PCIe 3.0 x4

I have two nVME M2 slots used on my motherboard by a Samsung 980 Pro and Sabrent Rocket M2. Also have 3 x Samsung 850 EVO SSDs connected via SATA. There is no loss of speed / ports
How is speed limited going by the chipset instead of CPU. I see similar speeds when connecting the same drive to M2_1 as I do connecting it to M2_2
 
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@Guest2 @Penfold101

Motherboard is only PCI-E 3.0. It's an Asrock B365m Pro4. https://www.asrock.com/mb/intel/b365m pro4/index.asp

This is just for a home server which is for file storage and a couple of VMs (nothing too intensive). It runs headless and has no GPU. The only current PCI-E device is a network card and TV tuner card.

Speed isn't a concern within reason - obviously I want it to be fast, but it doesn't need to be NVME fast. I have saturated all the onboard SATA with hard drives and one is taken up by the second SATA m2 slot. I'm hoping to reclaim this by moving the SSD to a PCI-E card.

I have some sata m2 drives lying around and only really need 2 m2 slots. Any extra would purely be a bonus. NVME would be nice, but isn't required.

I hope that helps.
 
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@Guest2 @Penfold101

Motherboard is only PCI-E 3.0. It's an Asrock B365m Pro4. https://www.asrock.com/mb/intel/b365m pro4/index.asp

This is just for a home server which is for file storage and a couple of VMs (nothing too intensive). It runs headless and has no GPU. The only current PCI-E device is a network card and TV tuner card.

Speed isn't a concern within reason - obviously I want it to be fast, but it doesn't need to be NVME fast. I have saturated all the onboard SATA with hard drives and one is taken up by the second SATA m2 slot. I'm hoping to reclaim this by moving the SSD to a PCI-E card.

I have some sata m2 drives lying around and only really need 2 m2 slots. Any extra would purely be a bonus. NVME would be nice, but isn't required.

I hope that helps.
I think your best and easiest option is to get the largest Gen4 x4 nVME drive you can find / afford and use M2_1 only. It will ‘only’ work at gen3 speed, but that doesnt matter and will mean you can use it in future when moving to a gen 4 board.
Something like a Samsung 980 pro

This is my 2TB Gen3 Sabrent rocket (PCIe 3.0 x4)

4XX8NvU.png


This is my 500GB Gen4 Samsung 980 pro (PCIe 4.0 x4)
I doubt I would notice the difference in speeds at all (other than benchmarking)

hvTXJc5.png
 
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Soldato
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I have an NVME drive for the OS which I'd like to retain as a separate drive. I'd like to use a different SSD as a write cache to the server. I need to use 2 drives for the write cache as the data is duplicated. I don't want to use the OS drive for this purpose. I'd like to reclaim the SATA connector, therefore, I see no other option than moving to a PCI-E card. In my main PC, I'd agree with you, but for my use case, it won't work.

For the second SSD, I'll probably just look for a used drive on the MM. It doesn't need to be enormous - I have a spare 500gb m2 drive, so will probably just get another the same size.

The SSDs will move data to the hard drives overnight and I won't be writing huge amounts of data. It's the speed and responsiveness, mainly for small writes, that I'm interested in - though relative to a normal hdd, even a slow SSD is magnitudes faster.

The 2 spare slots would give the option to expand in future for a different purpose if necessary.
 
Soldato
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I have an NVME drive for the OS which I'd like to retain as a separate drive. I'd like to use a different SSD as a write cache to the server. I need to use 2 drives for the write cache as the data is duplicated. I don't want to use the OS drive for this purpose. I'd like to reclaim the SATA connector, therefore, I see no other option than moving to a PCI-E card. In my main PC, I'd agree with you, but for my use case, it won't work.

For the second SSD, I'll probably just look for a used drive on the MM. It doesn't need to be enormous - I have a spare 500gb m2 drive, so will probably just get another the same size.

The SSDs will move data to the hard drives overnight and I won't be writing huge amounts of data. It's the speed and responsiveness, mainly for small writes, that I'm interested in - though relative to a normal hdd, even a slow SSD is magnitudes faster.

The 2 spare slots would give the option to expand in future for a different purpose if necessary.

Are right, didnt know you had 1 nvme drive already as the OS drive.
There is another option - New motherboard, CPU and RAM! Then you get 3 (or more) on board nvme slots that support PCIe 4.0.

Failing that, the PCI-e card should be fine as you don't require high GPU bandwidth

Someone may know something I dont, maybe a card / m2 adapter exists that can be connected into the PCI-e x16 slot where the GPU usually goes. That may allow for 4 x high speed m2 slots, without taking up any of the SATA ports
 
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So, if you want more NVME drives, you need an expansion card and you need 4 lanes per drive. The ASUS card, and any card which has 4 slots on it, would need 16 lanes to itself to address all 4 drives, so you’d have to forego a GPU or get a thread ripper (many, many lanes...) At best you can run your GPU at 8x and have 2 drives on the ASUS card using the other 8x lanes.

One of the reasons I've stuck with my older X79 platform - plenty of PCI-e lanes and I don't have to sacrifice any GPU bandwidth to run a second slot at x16 (or can do 1x x16 + 2x x8, etc.)
 
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Someone may know something I dont, maybe a card / m2 adapter exists that can be connected into the PCI-e x16 slot where the GPU usually goes. That may allow for 4 x high speed m2 slots, without taking up any of the SATA ports

yup, this is the ASUS Hyper X add in card, which comes in PCI 3 and 4 variants. It’s supports up to 4 NVME drives. But each one requires 4 lanes so it takes up the 16x GPU slot. Other manufacturers do the same but with a switch on board so you don’t need all the lanes, but they’re like 10x the price...
 
Soldato
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I currently only have 2x PCI-E 1x devices. Sounds like the Asus Hyper X does what I need. Thanks all.

A couple of final questions;
I presume the newer PCI-E 4.0 card is backwards compatible with 3.0?
I presume the m2 slots also support SATA ssds without taking up any of the onboard sata ports? ie they don't just supply power and require a SATA cable to the motherboard like some of the cheaper cards I've seen?
 
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lol, I never even looked at costs, I just remembered Addonics are a bit of a leader when it comes to creating these kinds of things (I have one of their 2x SATA m.2 and 1x PCIe m.2 cards) and I also know startech re-brands their stuff, although you're right, startech tend to be overly expensive for no reason.
 
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I’m thinking that because it supports multiple different M2 form factors, it just NVME, and has a massive heat sink of it, that it uses a switch or some sort of processor on the card to control it, hence the extra cost. The Hyper X just directly connects the drives to the PCI slot.

Or they could just be pulling a fast one...
 
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I "think" you're partially right.

I don't think it's a complicated scenario for NVMe or whatever, being that it's a PCIe protocol connection, I suspect mainly a pass-through type of affair.
It seems to been 8x speed, so no fancy switching there.
They used to do a card capable of 110 length drives, 2x SATA and 1x PCIe and that one had an extra SATA power plug to spread the load, and was described as for more power hungry cards (and there was 3)
I didn't look too closely, but there maybe a RAID chip/option on that card, so perhaps the heatsink is to cover the power stages and that?? on closer inspection, it looks like you have to use software RAID so no hardware onboard, so i'm at a loss as to why that has a sodding great big heatsink on it!

Startech and prices - yup, they just over charge, they make some really cool things (or should I say they re-brand some really cool things) like the card I used in a build a few years back, that too was an Addonics card, 2x SATA m.2 sockets on one side and a single m.2 PCIe socket on the other, 4x PCIe connection and worked really well (didn't suggest it here as it uses the motherboard SATA and you have to connect 2 cables to it) only differences between the one I used and that startech sell and the earlier one I mentioned which seems to have been an update was, no extra power connector, and only 80mm length drives supported, oh and the activity LEDs were on the back plate, with no connection for case activity LEDs ....... Startech still sell the one I used (PEXM2SAT32N1) although Addonics has discontinued both this and the previous card I mentioned, but I think on amazon it's about £34 a fair bit more than I paid for the Addonics version, I think that was something like 19.99 and Startech themselves list it at £45.99 :eek:
 
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I was about to come and say exactly what you’ve said in the edit mate :D

I reckon it’s just an older way of doing things that no-one has bothered to change the price on - you can get single drive adapters for like £15 and any more than that you may as well just get the Hyper X knowing that if you want to use more than two drives in the future you’re already covered! For the OP it’s the obvious solution as he doesn’t have a GPU in the first place - everyone is learning things!
 
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It is costly due to the use of the PCI-e switch which gives four x4 connections from a single x8 link. Though those chips should be cheaper now.
 
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