I have an MSI laptop with a Toshiba SSD 256GB (thnsnj256g8nu) and I want to upgrade it to an Evo 970 plus.

The old SSD fits perfectly but the new one doesn't, like it's 2mm bigger.


Old Toshiba SSD

Old Toshiba SSD

The Problem The problem

Why is it not compatible, and how can I know what items are compatible with my motherboard? Should the new SSD fit in the motherboard?

  • 2
    Does your laptop support B or M keyed M.2 devices? You will have to take a look at the connector to determine this information. Instead of submitting a comment you should provide the information within the body of your question. However, both SSDs are the identical length and width, which means the only possible explanation is due an incompatibility with M key. It also looks like you are attempting to install the Samsung drive in the incorrect orientation.
    – Ramhound
    Mar 5 '20 at 11:56
  • How to know if my laptop does support M or B? I have this MSI msi.com/Laptop/support/ge62-2qf-apache-pro Note: I just flipped the SSD so it fits slot separator
    – Adam
    Mar 5 '20 at 12:00
  • 2
    Visual inspection of the connector
    – Ramhound
    Mar 5 '20 at 12:09
  • 3
    Your link does not actually work. What is the exact model number of your laptop? It appears you are trying to replace a SATA M.2 drive with a NVMe M.2 which isn't going to work.
    – Ramhound
    Mar 5 '20 at 12:27
  • 1
    I clicked the link, page goes to a 404 error, the link you provided in your comment is not functional. Comments are designed to be temporary. if you had provided that information in the question you could correct the link. The only recourse you have is to just delete the comment since the link is not valid and it cannot be edited.
    – Ramhound
    Mar 5 '20 at 14:42

According to the picture you posted, the old model you used was a Toshiba THNSNJ256G8NU and it's a SATA III SSD. It uses a "B+M" key edge connector, according to the picture you posted.

Here is what the "B+M" connector looks like:

enter image description here

Meanwhile, the new one you purchased and plan to replace it with is an NVMe SSD (Samsung Evo 970). It uses an "M" key connector.

The first thing you should check is whether your laptop supports NVMe SSDs or not. Many laptops only allow using SATA SSDs, only having a SATA III interface. Therefore, even if you can insert this new SSD into your M.2 slot somehow, it may not work at all.

I couldn't find full specifications of your laptop based on the model you posted.

The best replacement for you is this one.


After digging a bit deeper, I found this file from MSI, which declared that an "M" key SSD can only be used in an "M" key socket:

enter image description here

A bit deeper in the same document:

enter image description here

So based on the model you provided, you have 2 "B" key SSD slots, and 1 "M" key SSD slot. However, all three slots can only use SATA III SSDs. There is no way you can use an NVMe SSD at all.

So the one you have purchased (Samsung 970 EVO Plus) can't be used.

  • If the GE62 2QF notebook can support Socket 2 (B Key) and Socket 3 (M Key) based on the screenshot. I base that statement on the fact you highlighted that specific text. I suspect either the MSI screenshot is incorrect or we have the incorrect screenshot However, there is no doubt, the author's current SSD is a M.2 SATA 3 (B&M Key)
    – Ramhound
    Mar 5 '20 at 14:48
  • I doubt that because the source was issued by MSI itself (from asset.msi.com). However, the one that Adam has purchased doesn't work with his laptop at all.
    – Echo Diaz
    Mar 5 '20 at 16:30
  • 4
    The screenshots are more confusing then helpful, which isn't you fault, but in one screenshot they indicate that Socket 3 is (M Key) but in the other they indicated the model has both (Socket 2 and Socket 3) and in the same screenshot indicates it only has SATA (Socket 2). MSI isn't known for it's documentation (my own experience caught numerous erratas).
    – Ramhound
    Mar 5 '20 at 16:56
  • Wonderfully knowledgeable answer.
    – Fattie
    Mar 7 '20 at 20:56

You have an incompatible drive and are trying to insert it upside down!

Unfortunately M.2 is a horrible mess. In theory M.2 supports a bunch of different keyings, with each keying supporting a different combination of interfaces. The two keyings relavent for SSDs are keys "B" and "M".

Unfortunately the B and M keyings are almost, but not quite a mirror image of each other. In your case you got lucky that your slot was tight enough to prevent the incorrect insertion. I saw a similar post over on hardforum where someone actually managed to insert a SSD upside down.

In theory the key B pinout supports "PCIe ×2, SATA, USB 2.0 and 3.0, audio, UIM, HSIC, SSIC, I2C and SMBus", while the key M pinout supports "PCIe ×4, SATA and SMBus ". In practice the two interfaces we care about for SSDs are PCIe and SATA.

In practice slots that only support Sata M.2 SSDs are usually B keyed, slots that only support PCIe are usually M keyed and slots that support both are also usually M keyed. PCIe M.2 SSDs are usually M keyed, while SATA M.2 SSDs are usually double notched to fit both B and M slots.

Your slot is B keyed, which in practice means you need a SATA M.2 SSD. In principle a B key slot could support PCIe x2, but even if it does, it doesn't really help you because most PCIe M.2 SSDs are M keyed.

  • 2
    I wouldn't say they got lucky on the slot size. The person on the other site who managed to cram an M key upside down into a B slot was unlucky as that's not supposed to be possible without a lot of force and breaking of things.
    – Logarr
    Mar 5 '20 at 22:23
  • 10
    Upvoted for "horrible mess".
    – Rich
    Mar 5 '20 at 22:36
  • 1
    Still not as bad as USB C.
    – user253751
    Mar 6 '20 at 10:52
  • 12
    A number of years ago I worked at a big-box computer store, and a customer came in asking for a 128MB PC-100 ram chip. What he didn't tell the salesman was that it was for a laptop, which used the smaller SO-DIMM chips. Easy mistake, anyone could have made it. We would've gladly refunded it, but this guy decided he was gonna MAKE it fit. He sawed the chip in half and filed a new notch in it to make it fit, predictably frying his laptop. He brought it back demanding we pay for the damages, but obviously it was his fault so we didn't. We framed the chip and mounted it on the wall. Mar 6 '20 at 16:47
  • @DarrelHoffman PC-100?! A number of years indeed...
    – J...
    Mar 8 '20 at 18:41

The Samsung Evo 960 Plus drive has a PCIe Gen 3.0 x4, NVMe 1.3 interface. Your Toshiba THNSNJ256G8NU drive has a SATA 6.0 Gbps M.2 interface.

Your replacement drive would be a Samsung 860 Evo.

  • 2
    I was actually mistaken. When I searched for THNSNJ256G8NU I got results for the incorrect drive on Amazon. THNSNJ256G8NU is actually a SATA M.2 drive which is the reason not fit in the slot. I have restored your original correct answer.
    – Ramhound
    Mar 5 '20 at 12:26

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