Using an NVME SSD in AHCI vs RAID mode

Jon9999 · 15 Oct 2016

I built my system with a Samsung 950 PRO m.2 NVMe SSD as the Windows 10 boot drive (C:), plus a pair of old-fashioned SATA-III hard drives configured in RAID1 as my data drive (D:). The SSD is plugged directly into one of the m.2 slots on my motherboard. I have the BIOS option for SATA controller set to RAID, using the built-in Intel RST RAID controller. And if it matters, Windows is running in UEFI mode.

Everything appears to be working fine, except that Samsung's Magician utility does not recognize my Samsung 950 PRO drive as an NVMe device, so it will not manage it. Within Samsung Magician, the Samsung drive's name appears garbled, with every second letter swapped: "aSsmnu gSS D59 0RP O15G2 B" instead of "Samsung SSD 590 PRO 512 GB." Everywhere else, including Windows System Properties, Disk Management, Device Manager, and Intel RST, the name of the Samsung SSD appears correctly. Samsung Tech Support told me to download the NVMe driver from their website and install it, but when I tried that, I got an error message saying that no NVMe drives could be found on my system.

I am gathering that for some reason, Samsung Magician refuses to work when there is a RAID controller managing the SATA drives, even if the Samsung drive itself is not configured as RAID.

My questions are these:

0) Is there a workaround to get Samsung Magician to work properly?

1) Does allowing the RAID controller to manage my Samsung SSD reduce the lifespan of the SSD? That is, since Samsung Magician does not recognize the drive, do I lose any protection on the drive or can it end up with unnecessary read/writes that will reduce its lifespan?

2) Same question, but for read/write efficiency. Does having my SSD under the RAID controller mean I will lose some of the speed I would otherwise get from the SSD?

3) Is there a way to separate the SATA bus so the Samsung SSD can be managed directly by AHCI, which still permitting me to have a RAID1 array for my other two drives? Or is it either AHCI or RAID for the entire system?

4) If keeping the system the way I have it will reduce the SSD's lifespan or efficiency, is having RAID1 worth it? I make separate backups of my data drive (I understand that RAID is not a backup strategy), but it's somehow comforting to know that I am protected against a drive failure. Or is RAID1 not really helpful in the modern world, so I may as well get rid of it so I can use Samsung Magician?

Thanks.

EdTittel · 17 Oct 2016

I have the same NVMe SSD (512 GB) and an Asrock Z170 Extreme7+ mobo. You might want to try sharing your questions with Les Tokar, the guy who runs the excellent TheSSDReview.com website (if you send me a private msg, I'll give you his email address). Here's what I've been able to figure out so far, by way of addressing your Q&A:

0) Is there a workaround to get Samsung Magician to work properly?
I just checked the Samsung downloads this weekend, and the Manual & Downloads page for this drive still lists Magician 4.9.7 as the current version. Inside that software, the program reports that OS Optimization for this SSD is not supported. I take that to mean the answer to your question is "No."

1) Does allowing the RAID controller to manage my Samsung SSD reduce the lifespan of the SSD? That is, since Samsung Magician does not recognize the drive, do I lose any protection on the drive or can it end up with unnecessary read/writes that will reduce its lifespan?
I don't think it's a problem. None of my health indicators have moved since I installed the drive in January, even after 5.24 TB of writes.

2) Same question, but for read/write efficiency. Does having my SSD under the RAID controller mean I will lose some of the speed I would otherwise get from the SSD?
Normally, if you run a single drive through RAID it works exactly the same as it would with AHCI. To me that means no difference. If you put multiple drives together in a RAID 0 array -- as Tokar documents in an SSDReview story earlier this year -- it runs faster overall. Again, I don't think this is a concern.

3) Is there a way to separate the SATA bus so the Samsung SSD can be managed directly by AHCI, which still permitting me to have a RAID1 array for my other two drives? Or is it either AHCI or RAID for the entire system?
You would want to install a RAID card to use RAID for other drives: the built-in RAID controllers on motherboards aren't really industrial strength anyway. But no, you can't run both AHCI and RAID on the same set of SATA controllers.

4) If keeping the system the way I have it will reduce the SSD's lifespan or efficiency, is having RAID1 worth it? I make separate backups of my data drive (I understand that RAID is not a backup strategy), but it's somehow comforting to know that I am protected against a drive failure. Or is RAID1 not really helpful in the modern world, so I may as well get rid of it so I can use Samsung Magician?
Even if you get rid of RAID the 950 still doesn't work with Magician. No reason to change things as far as I can tell. Think of the old Bobby McFerrin song: "Don't worry, be happy!"

--Ed--

Jon9999 · 17 Oct 2016

Thanks, Ed!

EdTittel said:

None of my health indicators have moved since I installed the drive in January, even after 5.24 TB of writes.

How can I check the health of my drive? S.M.A.R.T. doesn't appear to work with a RAID controller, and Magician doesn't tell me much since it doesn't recognize the drive as NVMe. What tool do you recommend?

EdTittel said:

Even if you get rid of RAID the 950 still doesn't work with Magician.

I mean I could get full Magician functionality if I were to de-RAID my hard drives and change the SATA mode in my BIOS from RAID to AHCI. (I know, I would need to take some extra steps to make sure Windows installs the AHCI driver -- but I think it's already installed because my CD-ROM is on a separate SATA controller on my motherboard, which is AHCI.) Is having RAID1 worth losing Magician for? Is RAID1 all that worthwhile overall anyway in 2016?

EdTittel · 17 Oct 2016

My understanding is that RAID when handling a single drive is the same as using AHCI. That's why I see no special advantages to switching back from RAID to AHCI (and also, my mobo doesn't recognize the drive in the UEFI drives listings on AHCI, though it will as a RAID device -- go figure!). As for access to smart data, Magician 4.9.7 happily shows me smart data for the 950, to wit:

Using an NVME SSD in AHCI vs RAID mode-950-smart.jpg

I think this is a relatively new, latest-generation development, so if you haven't upgraded Magician yet, this may make it worthwhile. OTOH, you can always use a tool like CrystalDiskInfo to access the SMART data from the drive instead.
HTH,
--Ed--

Jon9999 · 17 Oct 2016

Ed,

This is very strange, because we're seeing entirely different things here. My whole issue is that Magician does not recognize my Samsung 950 PRO as a Samsung NVMe drive, while yours appears to recognize it.

Compare what I see in Magician 4.9.7 with what you see. My drive is listed as "aSsmnu gSS D59 0RP O15G2 B" (with every 2nd letter swapped), while yours lists it correctly as "Samsung SSD 590 PRO 512 GB." (If you Google "aSsmnu," you get lots of hits from people in the same bucket as me, but no solutions that I can find.) My drive doesn't have the "Genuine" badge next to the serial number that yours has. My Drive Health Status, Total Bytes Written, and AHCI Mode are all "N/A," while yours actually say something. The S.M.A.R.T. button in my Magician brings up an empty grid, while yours is populated. You appear to have access to the other functions in the left-hand-side navigation menu, while in mine, every link except "Disk Drive" and "Performance Benchmark" is deactivated. Oh, and mine shows the drive capacity as 0.00GB in the two textual places, but 453 GB in the cartoon.

Using an NVME SSD in AHCI vs RAID mode-1.png

Using an NVME SSD in AHCI vs RAID mode-smart.png

Using an NVME SSD in AHCI vs RAID mode-2.png

I wrote to Samsung, and the answer I got just this morning (slowly, over several days, and after several back-and-forths) was that Magician does not work with RAID mode. So how come yours seems to work if we have very similar setups? How can I get to be like you?

EdTittel · 17 Oct 2016

Ahhh, now it all makes sense. I *AM* running on AHCI rather than RAID. And now we both know why you might want to switch. I never used RAID in the first place because it didn't make sense to me to add a whole new layer of software for something my single NVMe drive wouldn't let me use anyway. The lightbulb just went off for me, and now you have a reason to switch.
Thanks for keeping at this with me: I think we've got it sorted now.
--Ed--

Jon9999 · 17 Oct 2016

EdTittel said:

None of my health indicators have moved since I installed the drive in January, even after 5.24 TB of writes.

This really worries me. Can you please confirm that number, Ed? You've been using the drive since January and have 5.24 TB of writes? I installed mine last week, and according to CrystalDiskInfo, I already have 1.822 TB of writes. (It's my system drive, if it matters.)

Using an NVME SSD in AHCI vs RAID mode-capture.png

Now I'm really worried...

EdTittel · 17 Oct 2016

You're going to take a big initial hit when you do the OS Install. I don't think you have cause for concern. according to Storage Review, it's got an MTBF of 1.5 million hours and a max write of 400 TB. You should be OK.
HTH,
--Ed--

EdTittel · 17 Oct 2016

You're going to take a big initial hit when you do the OS Install. I don't think you have cause for concern. According to Storage Review, it's got an MTBF of 1.5 million hours and a max write of 400 TB. You should be OK.
HTH,
--Ed--

PS: going back to check, I bought the drive in January, but I didn't get around to building the system with the 950 in it until sometime in February, as this blog post reveals: Woo hoo! NVMe Boot Speedup Achieved - Windows Enterprise Desktop.

Jon9999 · 17 Oct 2016

EdTittel said:

PS: going back to check, I bought the drive in January, but I didn't get around to building the system with the 950 in it until sometime in February

Still, 9 months vs 1-2 weeks and only 1/5 as many writes. I'm very concerned.

You've been a great help, Ed. Thank you.