does it matter what m.2 slot i use

AMBIL SEKARANG

What are PCIe Slots and Their Uses? - Beginners Guide

I have an Inspiron 3250. It has a PCIe x16 slot which is currently empty. Can use it to add an NVme PCIe M.2 SSD using NVMe PCIe3.0 x16 M.2 SSD expansion card?

eGPU TB3 Extension Cable

What I know already that NAD9 comes with MXM 3.0 slot if u don't use it with multi M.2 adapter then u could buy an MXM to PCIE X16 adapter for the same price from superbuy and take the full bandwidth speed.

What can I plug into a pcie 2.0 x16 slot? | Tom's Hardware Forum

Running a z97 Sabertooth Mark 2 (the one with usb 3.1). There's a black slot at the bottom of that board, pcie 2.0 x16. The manual says it maxes out at x4 though, I don't understand what that means (3.0 x4 speeds?) I want to use that slot for something, but I don't know what. Can I use a 3.0...