Samsung SM951 PCIe M.2 512GB SSD Review

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hst101rox

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You may have something there. I was just going by the 70K random write, 90K random read stat in the specs. For instance the Samsung 850 EVO is specced at 88K or higher for random reads and writes at QD32, 10K random read @QD1.
I wonder what queue depth that was measured at.

It would be very helpful to have a regular 850EVO/PRO, OCZ Vector or similar to compare it with rather than al PCI-express SSDs.
 


Never had that problem. I think you might have a virus or something.
 

MrCommunistGen

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Sadly, Apple uses their own proprietary connector for their PCI-E SSDs.
 

bit_user

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Congratulations! You've just discovered why NVMe was created!

This is a AHCI drive, so it's going to be held back by ACHI's bottlenecks.

You act as though the OS only reads 4k at a time. Sure, some config files will be around 4k, but most executables, DLLs and shared libraries are hundreds of k or even megabytes. Then there are data files, such as fonts. Just eying the truetype fonts on my Windows 7 box, they seem to range between a few hundred k and a couple megs.

I'm not saying the drive would make a huge difference, but I'd expect it to be measurable.
 

hst101rox

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Thanks for letting me know about NVME. So we have not only m.2 that uses AHCI SATA, and m.2 that uses AHCI PCI-express, but also m.2 that uses NVME PCI-express?
I hope everything switches over to the latter for the benefits.
 


AHCI and NVMe are protocols, basically how the drive is managed by the system. PCI-Express is a physical interface, mostly just how the raw data is transferred. Pure PCI-Express was never really designed to carry storage data, it was meant for expansion cards and communication between CPU and chipset etc.

That's also why boot support for raw PCIe SSDs has been lacking, though it's getting better now.

Anyway, AHCI was mainly used on the SATA connection. Now we're moving from SATA to PCIe connections, and NVMe is designed to run on top of PCIe and get the most out of SSDs (and should also offer more straightforward boot support).

This is also why I was so disappointed to see that the SM951 does not support NVMe, despite Samsung promising NVMe support.
 

robisinho

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why does the article claim that this is not samsung's 3d "v-nand" tech? It really seems that it must be.

There are only 4 chips total. NAND chips are measured in Gb — gigabit. This is a 512GByte device so we have 512 * 8 (converting bits to bytes) / 4 = 1024Gb chips. That's before accounting for overprovisioning. The only technology that can go that high is V-NAND. Most 16nm NAND is still in the 64Gb and below category .. there might be some ticking a bit higher in some special use cases (128Gb I think I remember hearing about) .. but this just can't be 16nm and single layer. It has to be v-nand.
 

childofthekorn

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it will. Been out in enterprise environments for awhile.
 

Haravikk

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I also wished they put a 850 pro in the charts to see the jump from the fastest sata to the PCIe-based M.2
The 850 EVO's performance is around 550mb/sec read, 470mb/sec write, so this new drive is a pretty big deal, with nearly four times the read speed on even the 128gb model. Its write speed isn't a huge upgrade, but the larger models definitely are.
 

That's only sequential performance, which is not as important as random IOPS. The XP941 was already far ahead of any SATA3 SSD on sequential performance, but was nothing special when it comes to random IOPS. The SM951 seems to have changed that, but a direct comparison would have been nice.
 

ifIwasarichman

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While the drive's performance is certainly impressive, the serving time graph shows what you really need to know: the performance will make practically no difference in the vast majority of consumer workloads. The only people who should be spending the premium for this drive are professionals who will regularly be transferring large files around. Anyone else is just wasting money, as any modern SSD will perform largely the same in practice, even if their benchmark numbers aren't as impressive.
While the drive's performance is certainly impressive, the serving time graph shows what you really need to know: the performance will make practically no difference in the vast majority of consumer workloads. The only people who should be spending the premium for this drive are professionals who will regularly be transferring large files around. Anyone else is just wasting money, as any modern SSD will perform largely the same in practice, even if their benchmark numbers aren't as impressive.
I would have to agree
Most people that have a reasonable ssd will not notice much difference, it will start shortly after you hit the start button and programs will open and run extremely fast for what they do..Not a lot of difference when the PC starts in a few seconds or about 10 seconds (as my Dads PC with a Crucial m500 - he is just happy that it does not take minutes like the old one used to with a hdd).
Hard core users - examples gamers and video editing - will notice, at times, a speed difference. But for general use (and most of my friends just use their computers for emails, social networking, for things like storing photos and music, or accounting) will not benefit the average user.
What I would prefer to see are larger ssd's - 2 or 4 TB versions.. If we could get 1TB masta, why not a 4TB 2.5" sata ssd with reasonably good speeds of somewhere over 500MB/s. or a 2 TB M2 with speeds of about 1000MB/s.
 

ifIwasarichman

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Nothing like this is easy.
I started with computers when there were only punchcards, no gui's, no operating systems. Things have gotten a bit better since then (at least now when entering code into a computer you don't have to worry about little tiny squares off the punchcards ruining the program Ha Ha), because people have taken on the hard jobs and found solutions. OK a lot of these solutions end up being expensive , but if there are people wanting these things, there is a market to sell them.
 

ngbeslhang

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Agreed. I just quite don't like that "sarcasm".
 

RamCity

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In this case, it should be, at least for Samsung, since they've been producing the 1TB PCIe SSD for the cylindrical Mac Pro for over a year now.
 

r0llinlacs

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Absolutely ridiculous pricing. Memory is in damn near EVERYTHING now, so why is it still so expensive? You can't tell me a different plug causes prices to skyrocket 500%. Insane. MAD because I have an M.2 slot I can't use because of these insane prices!
 

ngbeslhang

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Not sure what you actually mean but I guess you meant RAM.
This is SSD, NOT RAM.
 


SSDs use flash memory, which is obviously a type of memory. It's just slower than the types of memory used for system RAM and VRAM, but also cheaper and capable of retaining information without power.
 

ngbeslhang

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My mistake then. :/
 

tigerwild

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Yes it boots, I use it as my main drive in msi gt72. Wonderfully fast. I am also Augmenting it with a 4 gig Ram disk (out of 32gigs) reduces write overhead ad from temp files and extends lifetime. I love this drive!
 

ifIwasarichman

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Nice to hear someone else using a ramdrive program.
These used to be used a lot then they sort of got forgotten.
Now, with a lot of devices not having a spinning hdd, but using flash storage drives instead, I would have thought that they would have been widely used.
I have been using Primo ramdisk for years, as it allows my system to only use what is needed. I have a intel NUC with no spinning HDD and 16GB ram, so it saves a lot of wear and tear with temp and cache files. My desktop has 32GB ram and I use it to also load programs like games. Much faster load times and this is only 1800MHz ram. I would like to try new quad channel DDR4 ram with 3333MHz (fastest I know of so far), but at the moment it is way to expensive setting up a new system. At well over $2000 Australian for 64GB 2666MHz DDR4 ram - how much will 64GB (even heard they may be capable of 128GB) of 3333MHz cost? - can only find 16GB (4x4GB) kits which are out of stock and are priced at over $1000 Australian.
Money, Money, Money, if I was a rich man.
 
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