You might have a solid, older desktop PC that handles tasks decently, but your storage needs are growing, and modern games and apps demand significantly faster speeds than old SSDs can provide you with. When looking down at your motherboard, you realize the nightmare: there are zero M.2 slots on the board, or the single M.2 slot you do have is locked to slow PCIe 2.0 speeds, which are barely faster than SATA drives.