XMP (Extreme Memory Profile)
Also written as: EXPO, memory profile
XMP is a preset stored on the memory module that tells the motherboard how to run it at its advertised speed. Without enabling it, a fast kit runs at a slower default.
Memory ships with a conservative default speed defined by JEDEC so it will boot in any compatible board. The advertised speed on the box — DDR5-6000, for example — is usually an overclocked profile, not that default.
XMP is Intel's name for that stored profile; AMD's equivalent on modern platforms is EXPO. Enabling it in BIOS applies the timings and voltage the manufacturer validated for that kit.
This is a one-time BIOS toggle, but it is genuinely required: a kit sold as DDR5-6000 will run at something like DDR5-4800 until the profile is switched on.