Samsung 850 Pro or Samsung SM951 on Asus Z97-Pro

Lord_Silver

Reputable
Apr 30, 2015
5
0
4,510
Hi.. so, I wanted to buy a Samsung 850 Pro (128GB)... but then, I've read an article about the new Samsung SM951. Now I'm confused. I have an Asus Z97-PRO motherboard. If I would use SM951 on M.2 slot on my motherboard, which would be the max read/write speed I would have?
Is it true that would be faster to buy a PCI-Express SSD adapter and use it in there?
Is it worth it or should I stay with the Samsung 850 Pro?
I've read, too, some things that on some motherboards the SSD is not bootable or something like that. On mine, I would install it and then can I install Windows on it without doing anything else? Or do I need to change some BIOS settings or something?
 
I would recommend the Samsung 850 Pro over the SM951. The 850 Pro's performance record is flawless.

I maintain the ssd database listed in a sticky at the top of this forum section. Here is the link:

http://www.johnnylucky.org/data-storage/ssd-database.html

The database contains basic information about the 850 Pro, the SM951 ACHI, and the SM951 NVMe as well as links to technical reviews. For the past month I think have read every technical review, news article, and press release about the SMP951 models as well as the new Intel 750 NVMe. In addition both Samsung and Intel have provided some additional information. According to technical reviews the new M.2 and PCIe ssd's generate some heat. Samsung and Intel both indicated their new ssd's require adequate cooling. Intel actually published a recommended airflow but at the moment I can't remember what the numbers are. I was surprised by that since the Intel 750 NVMe has a large heatsink and is mounted on a PCIe card. For pc enthusiasts and gamers familiar with system ventilation, airflow, and cooling this should not be a problem. I am thinking something simple like a case side panel with an intake fan would be a good solution.

The second problem is there still is no manufacturers warranty for the SM951 because the 951's are OEM only. On the positive side RamCity, the Australian vendor that is selling the 951's, publically stated on their web site they will honor the 3 year warranty.

In the meantime, Samsung also released their 850 EVO M.2 SATA 3 ssd. This morning I learned that the 850 EVO M.2 will throttle back performance if temperatures get too warm. That information is straight from Samsung. I do not know if that applies to any other models or not. I sent out a few inquiries today. Hopefully we can get a clarification on that.

The point to remember is that these new ssd's require adequate cooling.

 

RamCity

Reputable
Feb 4, 2015
30
0
4,560


Call my view biased if you like, but if the heat generated by PCIe M.2 SSD's really was a problem, we'd all be reading about the disgruntled users on forums. The XP941 has been out for 18 months now and with nearly 10,000 units sold, we still we haven't had a return due to any heat issue, whether real or perceived. Sure they get do get warm if you blast them with benchmarking software, but the controllers are designed to handle it, and due to their small size, they still generate less actual heat output than a standard hard drive does.



Let's put this 'problem' in a bit more context as well. The Samsung XP941/SM951 IS covered by a manufacturer warranty, but being an OEM product, the warranty only extends to the system integrator, which is us. In fact, we are way more generous with how we handle warranty issues than any manufacturer would be. If you do have an issue, we just swap it out from our own stock right away and handle the return to Samsung separately. If you buy one from our Amazon store, it's just as easy as Amazon are renowned for their generous return policy.

Rod
 

Theodwros Tenizis

Distinguished
Jul 19, 2014
123
0
18,690
I think he is trying to say that before moving on a pcie/m.2 ssd stay with the 850 Pro. This kind of ssds are not very common now so imo you should wait until we have some more pcie/m.2 ssds so you can affort them easily like a common ssd now. Have patience, technology changes day by day. As an advice and even better than the 850 Pro buy 2 of them and strip them.
 
RamCity - Tom's Hardware published the very first review of a Samsung solid state drive in 2006. It was a Samsung prototype. The ssd had a lot of problems and Tom's Hardware sent it back. Samsung returned to the drawing board and came up with a new and improved design. The rest is history. I have routinely recommended Samsung ssd's without hesitation.

The temperature problem really does exist. I have been aware of it ever since the first problems surfaced when Intel released the 525 mSATA ssd in January 2013. It is nothing new and it is fairly well documented. The problem continues to exist with M.2 ssd's. There is a reason why Samsung and Intel require adequate airflow for their newest ssd's. Intel actually published airflow requirements for their new 750 PCIe ssd - 100 linear feet per minute for the 400 GB model and 300 linear feet per minute for their 1.2 TB model. Samsung simply published that their newest ssd's require adequate cooling. Unfortunately Samsung did not publish any cooling specifications.

The requirement for adequate airflow was not the only solution. Samsung and Intel did something else. What happens when an ssd overheats? In extreme situations the ssd simply stops working until the temperature is reduced to an acceptable level. In order to prevent that from happening both Samsung and Intel throttle or reduce ssd performance. Here is a link to the latest information for the Samsung SP951 ACHI model which clearly shows how temperature affects performance:

http://www.legitreviews.com/samsung-sm951-512gb-m-2-pcie-ssd-review_161689/3

Here is a link to more temperature information and thermal images:

https://www.pugetsystems.com/labs/articles/Samsung-XP941-Plextor-PX-G256-M6e-M-2-Qualification-575/

The bottom line is heat can and does affect ssd performance.

As for the warranty, I did mention in my original comments that Ram City honors the 3 year warranty.
 

CRamseyer

Distinguished
Jan 25, 2015
425
10
18,795
Heat is not an issue with either the Intel SSD 750 or the Samsung SM951. On the Intel you will need some positive air pressure in your case so air passes over the heatsink and exits the back through the perforated backplate. The SSD 750 runs very cool, even 1.2TB model that Intel recommends 300 LFM.

The Samsung SM951 runs even cooler. These products don't start to heat up until you really pound on them. Under normal workloads 99% of the installations will be fine.

The Lenovo SM951 does throttle at a lower temperature than the SM951 RamCity sells. You can even see the throttling in the review here at Tom's Hardware, look at the 128K Sequential Write test.
 

pdegan2814

Distinguished
May 29, 2014
20
17
18,515


The SM951 may certainly be faster, especially in benchmarks, and especially the NVMe version once you're able to get your hands on it. There are certainly things you need to take into account to make sure you're able to boot off it, however. For Asus boards you usually have to choose between enabling the M.2 slot or some PCI slots in the BIOS. Plus if you're installing Windows on an NVMe drive, you either need Win8.1+, or you need to load a driver during install.

Once you get above a certain level, the actual benefit of the added performance is less and less meaningful unless you are a serious power user or you spend your days running disk benchmarks. The 850 Pro is quite a bit cheaper than the SM951's I currently see for sale, and I think those are the AHCI version, dunno if the NVMe version will be more expensive. I currently have an 850 Pro in my system and I love it. Based on current prices, I doubt I'd choose the SM951-AHCI over the 850 Pro. We'll see what the price of the SM951-NVMe looks like. Samsung says at some point in the future the SM951-NVMe will get their 3D V-NAND, that should make things very interesting indeed.