M.2 nvme vs SATA 3?

ssal

Active Member
Why do people want to use a M.2 SATA 3 instead of the nvme? The former is not cheaper, but a lot slower, right?

And why do MB like the ASRock B460M has two M.2, but one of them is a SATA 3? Why not make them both for nvme?
 

Intel_man

VIP Member
Here are some reasons:
  1. M.2 SSD's on the SATA controller is still usually cheaper than the M.2 SSD's on nvme.
  2. Some people don't know the difference or aren't aware that M.2 only describes the form factor and not the performance and subsequently buy SATA m.2 drives.
  3. space limitations may restrict some use case from connecting a 2.5" drive and revert to a m.2 form factor. In this case, they may not need the performance gains nvme has to offer, so why put extra $ into something you won't necessarily reap the benefits for.
Personally, I wouldn't waste m.2 space for a SATA drive, but some will for weird niche reasons.

As for your question about Mobo slot configuration. It's a flexibility thing. The 2nd m.2 slot usually shares pci-e lanes to the PCH so you can either connect 2 SATA drives to it using the SATA connectors (usually SATA ports 5, 6), or connect a m.2 sata/nvme ssd to the 2nd slot. This is why you'll see in the mobo user guide that tells you if you connect to the 2nd m.2 slot, SATA 5, 6 cannot be used. So this flexibility of configuration really depends on the motherboard vendor as AMD/Intel typically only prescribes a percentage of the total PCI-E lanes to very specific tasks and leaves the motherboard vendors to decide what they want to include on the motherboard.
 

ssal

Active Member
Here are some reasons:
  1. M.2 SSD's on the SATA controller is still usually cheaper than the M.2 SSD's on nvme.
  2. Some people don't know the difference or aren't aware that M.2 only describes the form factor and not the performance and subsequently buy SATA m.2 drives.
  3. space limitations may restrict some use case from connecting a 2.5" drive and revert to a m.2 form factor. In this case, they may not need the performance gains nvme has to offer, so why put extra $ into something you won't necessarily reap the benefits for.
Personally, I wouldn't waste m.2 space for a SATA drive, but some will for weird niche reasons.

As for your question about Mobo slot configuration. It's a flexibility thing. The 2nd m.2 slot usually shares pci-e lanes to the PCH so you can either connect 2 SATA drives to it using the SATA connectors (usually SATA ports 5, 6), or connect a m.2 sata/nvme ssd to the 2nd slot. This is why you'll see in the mobo user guide that tells you if you connect to the 2nd m.2 slot, SATA 5, 6 cannot be used. So this flexibility of configuration really depends on the motherboard vendor as AMD/Intel typically only prescribes a percentage of the total PCI-E lanes to very specific tasks and leaves the motherboard vendors to decide what they want to include on the motherboard.
M.2 SSD is actually more expensive than than the 2-1/2" SSD. There is not too many choices. Maybe it's a limited supply while 2-1/2" is plentiful.
 

Intel_man

VIP Member
M.2 SSD is actually more expensive than than the 2-1/2" SSD. There is not too many choices. Maybe it's a limited supply while 2-1/2" is plentiful.
No where in my previous post did I mention M.2 SATA drives aren't more expensive than their 2.5" SATA counterpart?

There's not too many choices because there's not many needs for a SATA drive in m.2 form factor.
 
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