SODIMMs aren’t the only form of notebook memory. In 2007, Intel Turbo Memory (ITM) debuted, featuring 1, 2, or 4GB of NAND memory mounted on a mini-PCIe card that installed in notebooks much like a SO-DIMM. The PC used this solid state cache to help load files faster. Sadly, ITM was plagued by driver problems and soon died. Today, some of ITM’s concepts live on in “hybrid” hard drives, which incorporate NAND memory.