MB spec question

[CarlBar]

I'm just doing another of my "check the bloody freaking obvious you noob" things that i like to do with basically everything.

 

A lot of MB's say that installing a device in a given M.2 slot will disable X sata lanes, often the number varying by the slot, but some MB's word it a bit vaguely and imply populating either of the Sata slots will disable the other SATA slot as well, i'm guessing thats just vague wording for the lulz.

 

Secondly, since some slots only disable 1 SATA slot, does that mean they have less peak bandwidth, (not that i expect that to limit performance in real terms any), or is it just down to how everything's wired up to the controller on the MB, (what i'd expect given how PC hardware standards are setup).

[NelizMastr]

The chipset and CPU have limited PCIe lanes, and the distribution of the chipset lanes is entirely up to the motherboard manufacturers. Some choose to disable more SATA ports than others because of this. It's usually one or two ports that get disabled.