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Keying on M.2 drives

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Hey thanks for this, I'm not following techquikie maybe I should start.

Thanks for that article. I'll have a read through it, but from my understanding now, a M drive will work in a M port, a B drive will work in a B port and a B+M drive will work in a B or a M port? and best setup for performance would be a M drive in a M port or a B+M drive in a M port? for the max theoretical  4 GB/s

That would be correct with the keying, as for getting the best performance setups the M keyed slot gives the capability of the full x4 PCI-E speed but in terms of limitations it is currently the flash or controllers itself that are holding it back. One of the best M.2 drives currently is the 950 Pro from Samsung.

I'm in the middle of researching a new build, and I've seen a lot of information about these m.2 drives. Great. 

 

Problem, none of the specs of the motherboards clearly state the m.2 keying used on the board. So the question is does the keying matter? For example if I used the Asus Z170-A board which I believe has M keying? and had a B+M keying M.2 drive would it still work?

 

Thanks in advance.

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I'm in the middle of researching a new build, and I've seen a lot of information about these m.2 drives. Great. 

Problem, none of the specs of the motherboards clearly state the m.2 keying used on the board. So the question is does the keying matter? For example if I used the Asus Z170-A board which I believe has M keying? and had a B+M keying M.2 drive would it still work?

Thanks in advance.

 

Welcome to the Forums!

 

Yes the keying is very important in determining what M.2 drive it is and if it will work in that slot, the M key is the full speed x4 PCI-E capability but if you have a drive that has a B and M key it will work inside of a M key:

https://www.pugetsystems.com/labs/articles/Overview-of-M-2-SSDs-586/

 

 

560px-M2_Edge_Connector_Keying.svg.png
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Hey thanks for this, I'm not following techquikie maybe I should start.

 

Welcome to the Forums!

 

Yes the keying is very important in determining what M.2 drive it is and if it will work in that slot, the M key is the full speed x4 PCI-E capability but if you have a drive that has a B and M key it will work inside of a M key:

https://www.pugetsystems.com/labs/articles/Overview-of-M-2-SSDs-586/

Thanks for that article. I'll have a read through it, but from my understanding now, a M drive will work in a M port, a B drive will work in a B port and a B+M drive will work in a B or a M port? and best setup for performance would be a M drive in a M port or a B+M drive in a M port? for the max theoretical  4 GB/s

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Hey thanks for this, I'm not following techquikie maybe I should start.

Thanks for that article. I'll have a read through it, but from my understanding now, a M drive will work in a M port, a B drive will work in a B port and a B+M drive will work in a B or a M port? and best setup for performance would be a M drive in a M port or a B+M drive in a M port? for the max theoretical  4 GB/s

That would be correct with the keying, as for getting the best performance setups the M keyed slot gives the capability of the full x4 PCI-E speed but in terms of limitations it is currently the flash or controllers itself that are holding it back. One of the best M.2 drives currently is the 950 Pro from Samsung.

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That would be correct with the keying, as for getting the best performance setups the M keyed slot gives the capability of the full x4 PCI-E speed but in terms of limitations it is currently the flash or controllers itself that are holding it back. One of the best M.2 drives currently is the 950 Pro from Samsung.

Thanks very much!!  just a short follow up question, regarding this. 

 

I'm using pcpartpicker to see any compatibility issues and when I choose a Asus Z170-A motherboard with that Samsung 950 m.2 drive, it states that one of the sata express ports will be disabled, but I'm having a hard time figuring out why?, see as the board supports m.2 PCIE mode and the m.2 drive interface is PCIE 3.0

 

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Most motherboards with m.2 PCI-E support also support m.2 mSATA. The drive will run by default as mSATA and thus block a SATA channel on the controller. If you swap the controller to the PCI-E bus in BIOS then the drive won't block off SATA channels.

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Most motherboards with m.2 PCI-E support also support m.2 mSATA. The drive will run by default as mSATA and thus block a SATA channel on the controller. If you swap the controller to the PCI-E bus in BIOS then the drive won't block off SATA channels.

ahh so it's just the default setting using the sata channel instead of the PCIE lanes.

 

Thank you.

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Thanks very much!!  just a short follow up question, regarding this. 

I'm using pcpartpicker to see any compatibility issues and when I choose a Asus Z170-A motherboard with that Samsung 950 m.2 drive, it states that one of the sata express ports will be disabled, but I'm having a hard time figuring out why?, see as the board supports m.2 PCIE mode and the m.2 drive interface is PCIE 3.0

 

-PIC-

 

As said it basically disables the sata express to be capable of the bandwidth needed, which was also one of the problems with very high end motherboards where if you enabled one feature you lost the rest due to PCI-limitations (mainly Z97).

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