I have M2 slot marked as M2X3 What type M2 SSD (SATA, PCIEx

On your board, only one slot is connected to the chipset, M2_1, so it should be easy to find out which drive is in that bus with HWiNFO64 Two

Before you buy an SSD, you should check which type of slot your computer is using An B key slot is only compatible with B+M key

m2 pcie 40 in 30 slot 2 SATA SSDs have two slots in the interface connector, while PCIe SSDs have only one slot in the interface connector Non-Standard PCIe SSDs

m2 slot screw Although both SSD types have small form factors, drives typically have higher storage capacities The dimensions of mSATA and SSDs This image shows