M.2 nvme sata visual difference.

pcpete

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I just noticed all sata m.2 drives have two notices and nvme one. Maybe there are exceptions to this but that is what I have noticed. Have you guys seen exceptions to this?
 
Sorry but do you mean connection wise B & M? Always check the system before purchasing a M.2 card to make certain of the configuration on the board. I wish they kept it standard in all systems.

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NVMe can come with two notches (B & M key). Not just SATA.

I had a discussion not long ago on how confusing this has become -

...and I tried a SATA drive in the NVMe slot. No fireworks and computer still runs although not with the SATA drive in the NVMe slot.
 
I understand how they work, the difference between nvme and sata. We do a high volume of computers and it is nice to see at a glance if it is sata or nvme. I have always had to pull out the magnifier two figure it out. I just realized sata seem to have two slots and nvme one. It seems to be a quick way to tell what the computer is using.
 
NVMe can come with two notches (B & M key). Not just SATA.

I had a discussion not long ago on how confusing this has become -
Thanks @Diggs. I wasn't confident that it was always this way, but since I have taken notice it seemed to be a pattern.

I wonder if optanes are unique?
 
NVMe can come with two notches (B & M key). Not just SATA.

I had a discussion not long ago on how confusing this has become -

...and I tried a SATA drive in the NVMe slot. No fireworks and computer still runs although not with the SATA drive in the NVMe slot.
That just means that the NVMe card can step down to use only PCIx2 bus instead of the x4 bus that only a M key card can use. I’ve never seen a mobo that supported that but it’s part of the spec.
 
Er, what? Which is it -- it runs or not?
Per his other thread, it would prevent the system from booting but it didn't fry the computer or the card. He should have been able to boot into bios but as I understand it the PC wouldn't even power up. (I may be incorrectly recalling that. - He had a lot more trouble than it should have been but that system is a P.O.S Dell)
 
@Diggs The whole problem with that system was not because it was"Optane" memory. Optane is simply a fast kind of chip. HOW it is interfaced is the issue. That system was set up with a 16GB buffer on the SATA drive. The buffer has to be turned on or off in BIOS or Windows and can only be done if the drive is present. Chances are once you disabled the buffer both of the drives mentioned in your OP would have worked. A buffer is yet a THIRD option for M.2 slots and only works if the chipset supports that function. Most don't.
 
There's plenty of standards. Do you have a problem that a PCI slot can take a wide variety of different devices from serial port cards to video cards? The slot is designed so that you can add a wide variety of different devices. It all depends on the mobo chipset and what bus lines they have connected to it.
 
That just means that the NVMe card can step down to use only PCIx2 bus instead of the x4 bus that only a M key card can use. I’ve never seen a mobo that supported that but it’s part of the spec.
I see these occasionally. I just got in a Dell laptop with a 2230 m.2 SSD that only supported PCI-e x2. It had an M+B key. I upgraded it with a 2280 PCI-e x4 SSD that only had an M key. Dell has a very intelligent design that allows you to remove a little piece of metal in order to adjust where the screw hole goes. It's got a notch for a 2230, 2240, 2260, and 2280 SSD. Of course, the board can't take advantage of x4 speeds but it operates at reduced speed just fine.
 
I see these occasionally. I just got in a Dell laptop with a 2230 m.2 SSD that only supported PCI-e x2. It had an M+B key. I upgraded it with a 2280 PCI-e x4 SSD that only had an M key. Dell has a very intelligent design that allows you to remove a little piece of metal in order to adjust where the screw hole goes. It's got a notch for a 2230, 2240, 2260, and 2280 SSD. Of course, the board can't take advantage of x4 speeds but it operates at reduced speed just fine.
If it was M key then it probably was running at x4. The B slot is only PCIx2. I've never seen a B sloted MVMe card but the spec supports it and the card @Diggs found was able to run either. Note that the cards can have multiple keys like B+M the slots NEVER are. They are either B or M. Can't be both.

SATA can be wired to either the B or M key but PCIx4 is only M and PCIx2 is only B. The assumption is that you want a slot able to take either a SATA or an NVMe card so the SATA is available on both PCI configurations.
 
If it was M key then it probably was running at x4
Oh yeah, doh! I thought it was slower than the 3400MB/s when I ran a speed test, but now that I'm thinking about it, that might have been the speed test I ran on the original x2 drive. The computer is gone now so I can't confirm.

These drives are confusing and frustrating. I suppose we should just be glad they're actually using removable SSD's instead of just soldering them to the board like they do so often with RAM nowadays. I just got in a 2 month old HP laptop that was over $1,000. It only came with 8GB of RAM and there's no way to upgrade it. This client NEEDS more RAM, so their only option is to throw it in the garbage and buy something else. This is intentional I'm sure to encourage people to throw away their computers and buy new more often.
 
No sh-t. Everytime I see a post about them on here I end up doing more research and learning more. Scott Mueller needs to update his books to cover the subject.
 
Scott Mueller needs to update his books to cover the subject.
I wouldn't hold my breath if I were you. He usually releases a new edition every 2 years and it's been 6. I think he just assumes that computer repair is dead or that it's gotten so complicated now that you can't fit it all in a single book.
 
I wouldn't hold my breath if I were you. He usually releases a new edition every 2 years and it's been 6. I think he just assumes that computer repair is dead or that it's gotten so complicated now that you can't fit it all in a single book.
I think he is just retired. He’s gotta be in his late 60s.
 
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