Which slot should I use for my SSD?

you have a PCIe SSD, you want it in an slot that has PCIe support Please

The new Mac Pro with M2 Ultra combines our most powerful Apple silicon yet with PCIe expansion for the ultimate in workstation-class performance

what happens if someone leaves money in a slot machine SATA SSDs and SSDs that use two PCI Express lanes tend to use keys B and M to maximize compatibility, since both connectors can deliver both

what slot machines are at hollywood casino 2 is a slot that can interface with SATA , PCI Express