M2 vs SATA express, which will become standard?

[poohbear]

Hey all, wanna hear your thoughts on which interface is most likely gonna become standard for SSDs in the future, M2 or SATA Express? both support 10gb/s transfer rates, but both aren't always offered in the Z97 mobos. Some have opted to go only M2, while others only Sata Express, and some offer both (rare). What are your thoughts on which standard will become standard and ubiquitous in the future & why? Does it effect your decision when purchasing a new mobo?

Thanks in advance for your thoughts!

 

[Cerb]

Both will. They are for entirely different devices.

M.2 SATA now handles SATA SSDs (I don't like it, and wish they'd done a clean break, but c'est la vie).
M.2 PCIe will handle future small SSDs.

SATA Express may or may not be used with M.2 devices.
SATA Express as a physical standard will remain used for 2.5" and 3.5" drives.

SATA Express has the advantage of being able to run DOS via firmware IDE emulation, so it will hang around for some time to come. Also, HDDs are too slow to need anything that regular old ATA and SCSI don't offer.

 

[cbn]

How do folks feel about M.2 development in PCI-E 2.0 x 2 format vs x4 (either PCIe 2.0 or PCIe 3.0)?

 

[Cerb]

How do folks feel about M.2 development in PCI-E 2.0 x 2 format vs x4 (either PCIe 2.0 or PCIe 3.0)?

Performance-wise? We're bordering on getting 2GB/s/lane mainstream, everybody has 500MB/s/lane, and anyone with decent hardware has 1GB/s/lane. It won't matter. The next shrink allowing faster SSD controllers, combined with being able to boot off of NVMe soon, has the potential to be excellent, though. PCIe just happens to carry the data.

I really hope for a lot of consumer software to start getting on the, "anti-caching" bandwagon, as low-latency SSDs become more common (instead of having big in-memory buffers of objects, work as much as possible directly on mapped files. You know all the, "in the old days, whole OSes fit on floppies, and in 1MB RAM" crap? Well, there is a grain of truth, there, in that hogging private RAM for data structures with binary objects is a Hell of a lot faster than using less RAM, but risking that the OS might not have the data in RAM right now. But, with 0.05-0.2ms access times instead of 10-20ms, and it's a different story.

 

[cbn]

Performance-wise? We're bordering on getting 2GB/s/lane mainstream, everybody has 500MB/s/lane, and anyone with decent hardware has 1GB/s/lane. It won't matter. The next shrink allowing faster SSD controllers, combined with being able to boot off of NVMe soon, has the potential to be excellent, though. PCIe just happens to carry the data.

I really hope for a lot of consumer software to start getting on the, "anti-caching" bandwagon, as low-latency SSDs become more common (instead of having big in-memory buffers of objects, work as much as possible directly on mapped files. You know all the, "in the old days, whole OSes fit on floppies, and in 1MB RAM" crap? Well, there is a grain of truth, there, in that hogging private RAM for data structures with binary objects is a Hell of a lot faster than using less RAM, but risking that the OS might not have the data in RAM right now. But, with 0.05-0.2ms access times instead of 10-20ms, and it's a different story.

Part of the reason I ask that question because I wonder how many manufacturers will even bother with PCIe 2.0 x2? (It is so close in performance to SATA 6 Gbps apparently)

P.S. I have a mobo with M.2 (PCIe 2.0 x2)

 

[bunnyfubbles]

I don't think either will become "standard" on the desktop, although I think M.2 might have an edge for being relevant longer.

SATA-e advantage is that its not much different from what we're used to with a SATA connector and cabling and thus not as limiting as M.2.

M.2's advantage is that it seems to be a format that is pretty set in stone and likely won't change or be replaced for a while, whereas SATA-e is clearly a stop-gap solution and would be in greater danger of being replaced by a future SATA successor while M.2 could stick around as supplementary interface.

But from a performance standard, PCI-e SSDs will easily trump (more like tromp) either one, which is why I don't think either M.2 or SATA-e have much chance at any sort of lengthy longevity .

 

[Cerb]

Part of the reason I ask that question because I wonder how many manufacturers will even bother with PCIe 2.0 x2? (It is so close in performance to SATA 6 Gbps apparently)

P.S. I have a mobo with M.2 (PCIe 2.0 x2)

Doesn't really matter. The advantage of M.2 using PCIe is removing the ATA/SCSI storage layers, much more than the bandwidth provided.

 

[Cerb]

But from a performance standard, PCI-e SSDs will easily trump (more like tromp) either one, which is why I don't think either M.2 or SATA-e have much chance at any sort of lengthy longevity .

M.2 is PCIe, in a compact form factor for mobile and SFF computers.

while M.2 could stick around as supplementary interface.

What should it be replaced with as a primary storage form factor family? If it is made supplementary, what will become primary? It's annoying in some ways, like the multiple incompatible form factors, but they are all here, agreed upon by many companies, and likely to stick around for a bit. A PCIe card SSD is and will remain an enthusiast and business only option, and will never be mainstream.

SATA-e will likely live and die with HDDs themselves. We can probably do just fine with one or two mobo ports, if SSDs get as big as fast as is being alleged for 3D NAND's near future prospects. If you look at SATA-e from the perspective of board-only connectors, it's really quite elegant. IoW, it happens to work for a desktop, but was clearly designed for servers with backplanes, allowing for SATA, SAS, and PCIe support all in one.

 

[Zodiark1593]

What I'd like to see in laptops is an integrated SSD on board connected via PCI-e (x16?). Should be easily doable as we've been doing the same with dGPUs in laptops for years, and even small laptops can still retain an HDD for mass storage + an optical drive. Even your 13" and 14" laptops will have both an HDD and the iSSD (think 64GB), and current iGPUs make the loss of the dGPU moot for non-gamers.

 

[VirtualLarry]

What I'd like to see in laptops is an integrated SSD on board connected via PCI-e (x16?).

Maybe not x16 (physically, that would require a large form-factor / connector), but M.2 PCI-E x4 3.0 comes pretty close to what you want.

 

[bunnyfubbles]

M.2 is PCIe, in a compact form factor for mobile and SFF computers.

M.2 is a small form factor implementation of the SATA Express interface, so both M.2 and SATA-e can effectively be PCI-e interfaces, so I'm not sure what your point is...

my point is that PCI-e SSDs can be made to exploit as many lanes as the biggest slots allow (i.e. 8-16x, not just 2-4x) and thus not be limited by a compact form factor, which also has the bonus of being able to fit quite a bit more NAND chips onto a PCI-e card than we can onto M.2's biggest allowable dimensions.

Now while I would agree that PCI-e SSDs are going to be enthusiast/business oriented devices, my argument would be that the desktop market in general is shrinking into enthusiast/business dominated niche as the mainstream becomes an increasingly SFF/mobile market.

The OP didn't stipulate, but it would be fair to say that M.2 is already a standard winner, at least for SFF/mobile, and the strength of that market just might be enough to bleed over and envelope the desktop market with demand for M.2 (heck, I have already seen plenty of people clamoring for M.2 support in new motherboards, completely ignorant of future NVMe SATA-e or PCI-e SSDs, but they want M.2 because that's what they know and thus that's what they think is the future)

 

[Cerb]

M.2 is a small form factor implementation of the SATA Express interface, so both M.2 and SATA-e can effectively be PCI-e interfaces, so I'm not sure what your point is...

Let's start by that being wrong.

M.2 is a physical form factor which exposes SATA and PCIe electrical interfaces. It has nothing to do with SATA Express (though it could use it).

M.2 is too small for HDDs, so I see no reason why you'd bother with SATA Express on them. What reason would there be? If you're going to use an old interface, just use SATA. If you're going to use a new one, but want current and older OSes to boot, make it an AHCI controller, like Plextor did. If only current and newer are fine, use NVMe. I'm sure somebody will, due to what some given SSD controller chip can do, make a SATA Express SSD in M.2, but it's a generally ridiculous idea.

my point is that PCI-e SSDs can be made to exploit as many lanes as the biggest slots allow (i.e. 8-16x, not just 2-4x) and thus not be limited by a compact form factor, which also has the bonus of being able to fit quite a bit more NAND chips onto a PCI-e card than we can onto M.2's biggest allowable dimensions.

That only matters in servers and workstations, though. Nobody else is able and willing to pay for what will be negligible gains (for now, anyway). Also, there aren't many controllers with more than 8 channels, which will make such a thing even more of a rarity.

Now while I would agree that PCI-e SSDs are going to be enthusiast/business oriented devices, my argument would be that the desktop market in general is shrinking into enthusiast/business dominated niche as the mainstream becomes an increasingly SFF/mobile market.

Which still allows for M.2. Mobos will probably commonly come with one slot, and you can already buy card adapters, too. I can very much imagine M.2 SSDs coming with PCIe adapter cards just like 2.5" ones can come with 3.5" brackets.

The OP didn't stipulate, but it would be fair to say that M.2 is already a standard winner, at least for SFF/mobile, and the strength of that market just might be enough to bleed over and envelope the desktop market with demand for M.2 (heck, I have already seen plenty of people clamoring for M.2 support in new motherboards, completely ignorant of future NVMe SATA-e or PCI-e SSDs, but they want M.2 because that's what they know and thus that's what they think is the future)

You are writing as if M.2 NVMe SSDs won't exist, when that is precisely why those mobos are routing PCIe lanes to the M.2 slot. If NVMe is the future, why do you think M.2 won't be a part of that?

 

[Zodiark1593]

Maybe not x16 (physically, that would require a large form-factor / connector), but M.2 PCI-E x4 3.0 comes pretty close to what you want.

I think I didn't detail that aspect. In most laptops, when a dGPU is used, the gpu chip itself and memory are all soldered to the mobo and connects through an internal PCI-e x16 interface. This occurs without a slot. What I'm proposing is doing the same thing as above, but with an SSD on the mobo itself instead of the dGPU.

This should have the effect of reducing cost for SSD use, increase performance, and keeping size down while still having both an SSD and HDD in the same chassis.

 

[poohbear]

Thanks for the info guys. So....if its all PCI~E based, then it doesnt matter if i go with Sata e or M.2, right? An adapter would be enough to resolve any interface problem? Eg 2 years later an ssd i want is M.2 only, but my mobo only has a SATA E plug, i can just use an adapter & the M.2 ssd will work fine, right?

 

[Cerb]

I think I didn't detail that aspect. In most laptops, when a dGPU is used, the gpu chip itself and memory are all soldered to the mobo and connects through an internal PCI-e x16 interface. This occurs without a slot. What I'm proposing is doing the same thing as above, but with an SSD on the mobo itself instead of the dGPU.

This should have the effect of reducing cost for SSD use, increase performance, and keeping size down while still having both an SSD and HDD in the same chassis.

An SSD and HDD in the same chassis already exists in every conceivable definition, and isn't too hard to get in really tiny form factors, if you really want it. But, most people don't. I have both in my mini tower, but given my storage growth, if a 2TB SSD got to at or under $300 any time in the next 5 years or so, I'd get rid of it, putting even "slow" data on the SSD. If going SFF or mobile, I'd use an external drive or network storage. If stationary SFF, networked drives would be sufficient, with GbE. External HDDs aren't too reliable (even assembling them yourself), but they beat internal notebook HDDs, IME (and for tablets, an HDD is a non-starter).

Cost-sensitive devices already use soldered-on flash storage. It's usually eMMC, but if cost allows, PCIe would work. UFS is already in the wings to replace eMMC, too. Even real Windows runs on eMMC (albeit running like shit, due to poor write speeds).

If it's expensive enough not to use low cost embedded flash, though, it's expensive enough to allow storage customization, replacement, and upgrading. Not everyone wants a Chromebook, and only Apple could charge high prices for crap like that and get away with it. Notebooks with mSATA or M.2 SSDs and 2.5" HDDs, using the SSD for caching, have been available from the major OEMs ever since mSATA came out. Before that, there were dual-2.5" notebooks with cache drives. That is preferred over soldering it in.

It's not a technical limitation keeping OEMs from integrating SATA or PCIe SSDs, but that there is a threat of market forces going against them if they do, since people expect to be able to swap those parts out (or, usually, have their computer guy do it), and that it could add overall costs that may be higher than the cost of adding a slot and buying the parts. It also allows the OEM to have choices in terms of what storage device they use from whom. Finally, it allows them to not have to R&D that part of the computer, which is not yet mature enough to do easily, for high performance SSDs like we have in our PCs.

 

[Cerb]

Thanks for the info guys. So....if its all PCI~E based, then it doesnt matter if i go with Sata e or M.2, right? An adapter would be enough to resolve any interface problem? Eg 2 years later an ssd i want is M.2 only, but my mobo only has a SATA E plug, i can just use an adapter & the M.2 ssd will work fine, right?

Among other options. You'll just need to be very precise about the device you are trying to get working.

http://www.addonics.com/category/ngff.php

That's what exists already, for internal PC use, and their prices should be the highest you'll see, not counting ripoffs. There are also SATA controller cards with integrated M.2 slots, and M.2 SATA to USB adapters, already out there.

 

[ShintaiDK]

The future is NVMe based M2 and new formats. Specially next year SATA will start to lose ground in laptops.

 

[biostud]

Since M.2 will be used in the mobile PC's it will stay for a long time, and it seems that most motherboard producers include a M.2 port on their medium/top end products. So I think it will be around for a long time, hopefully the SSD producers will start to make more M.2 drives.

 

[poohbear]

Its interesting some of you are commenting laptops & "mobile PCs"(is that another term for laptops?) will dictate the new standard for desktops. So if M.2 is the more popular format it will become the new standard even for desktops. So the SATA creators/group have lost their influence in dictating interface standards? We'll see how it all pans out...for now i guess its safest to get a mobo with both interfaces.

 

[ShintaiDK]

Its interesting some of you are commenting laptops & "mobile PCs"(is that another term for laptops?) will dictate the new standard for desktops. So if M.2 is the more popular format it will become the new standard even for desktops. So the SATA creators/group have lost their influence in dictating interface standards? We'll see how it all pans out...for now i guess its safest to get a mobo with both interfaces.

M.2 supports SATA. Its actually more about what the future standard will be. Not the format itself.

SATA is penalized with its "HD" design. While NVMe will let SSDs run with their full potential.

100 series desktop chipset will support up to 3 M.2 NVMe devices as well as SATA and SATA Express.

 

[Vapid Cabal]

Performance-wise? We're bordering on getting 2GB/s/lane mainstream, everybody has 500MB/s/lane, and anyone with decent hardware has 1GB/s/lane. It won't matter. The next shrink allowing faster SSD controllers, combined with being able to boot off of NVMe soon, has the potential to be excellent, though. PCIe just happens to carry the data.

I really hope for a lot of consumer software to start getting on the, "anti-caching" bandwagon, as low-latency SSDs become more common (instead of having big in-memory buffers of objects, work as much as possible directly on mapped files. You know all the, "in the old days, whole OSes fit on floppies, and in 1MB RAM" crap? Well, there is a grain of truth, there, in that hogging private RAM for data structures with binary objects is a Hell of a lot faster than using less RAM, but risking that the OS might not have the data in RAM right now. But, with 0.05-0.2ms access times instead of 10-20ms, and it's a different story.

:thumbsup: AMEN brotha!