Intel XMP is an automated overclocking technology that enables motherboards to configure memory settings above and beyond the basic rated speeds of the PC industry, which are often significantly slower than the speeds that are actually achievable with a few clicks and compatible hardware.
New PC builders and upgraders without experience with XMP often wonder why their memory doesn't run at its advertised speed or data rate. High-speed memory that operates outside of industry standard specifications doesn’t get automatically configured when plugged into most systems. Realizing that most users won't manually overclock their memory to reach its rated above-standard rating, Intel developed an extended configuration table that’s stored on each compatible memory module’s EEPROM (a tiny flash storage chip), alongside the industry-standard settings which the memory will usually default to when first installed.
The information contained within this table extension is called an Extreme Memory Profile (XMP), and it includes such things as higher-than standard speed (data rate), lower-than-standard response time (latency), and any additional voltage needed to make the memory stable at these higher settings. Shown above is a CPU-Z screen shot of the configuration reading from a set of memory that supports both an increased data rate (DDR4-3200) and a decreased latency set (DDR4-2666 C15). Based upon DDR4-2666 C17 integrated curcuits (ICs), this kit needs the motherboard to increase its DIMM voltage from 1.20V to 1.35V to run reliably at its highest XMP data rate.
How Do I Enable XMP?
XMP mode is a firmware (UEFI) setting for compatible boards, which usually means that users must enter their firmware’s UEFI or BIOS and either click an icon or select XMP from a menu. Each motherboard brand develops its own UEFI interface, and users are often required to enter an overclocking menu. Entering UEFI is usually as easy (or as difficult) as tapping the Delete key during system initialization, before the OS begins to load. Some motherboards use other keys, such as F2, and some users are forced to tap the correct key in rapid succession after powering on simply to catch the short window between firmware and OS initialization. If need be, consult your motherboard or system manual for details about how to access the UEFI/BIOS.
ASRock motherboards, for example often include both an Easy and Advanced graphical user interface (GUI). XMP, being a fairly simple overclocking process, is present on the main screen of they company's easy interface, and also within the DRAM Configuration submenu of its OC Tweaker menu in Advanced Mode.
Asus also offers XMP in its easy GUI, but it’s the baseline setting for CPU overclocking within the Extreme Tweaker menu of Advanced Mode.
Biostar’s XMP selection is found within its O.N.E. (Overclocking Navigator Engine) menu, and EVGA’s within its Memory menu.
Gigabyte’s Easy Mode offers one-click XMP. This setting is also available within both the Advanced Frequency Settings and Advanced Memory Settings submenus of its Advanced Mode M.I.T. (Motherboard Intelligent Tweaker) menu.
MSI’s easy XMP button (the icon circled in the images above) persists through both its easy and advanced GUI, with a secondary setting made available to overclockers in Advanced Mode.
Supermicro’s consumer boards offer an XMP setting on the single-page EZ Mode menu, as well as the Memory Overclocking submenu of its Overclocking menu within Advanced Mode.
Exceptions, Exemptions, And Limitations
A member of the industry that develops manufacturer-agnostic memory standards, AMD's hardware doesn't always support Intel's nonstandard XMP settings. Major motherboard brands have attempted to reconcile AMD’s increased latency by adding a few cycles to the various timings specified in XMP. Asus calls this compromise D.O.C.P., and MSI calls it A-XMP: Builders should pay careful attention to our findings for each board in our reviews, since no two AMD boards produce identical maximums. If you’re looking for generalizations, most X470 motherboards will support at least DDR4-3467 when paired to a Ryzen 7 2700X. Most lesser chipsets and CPUs will work with at least DDR4-2933, and there’s a great number of products that fit between these minimal maximums.
Motherboards and processors that don’t support any overclocking will not support memory overclocking, even if it’s automated via Intel XMP. This includes models that use Intel’s H, B, and Q-series chipsets, as well as Intel’s non-K-series processors. Current “locked” CPUs and motherboards are limited to DDR4-2666, previous-generation parts to DDR4-2400, and the Core i3 (even the “unlocked” version) to DDR4-2400.
Other limitations include motherboards that can’t support the voltage adjustment required by many XMPs, those with poorly-written firmware that won’t set the proper advanced timings to make the system bootable (we’ve seen some boards set zeros for timings not addressed in XMP), and the chance occurrence of receiving a CPU that isn’t stable at normally-achievable overclocks. XMP is an overclocking technology, and support for higher-than-standard data rates isn't guaranteed by the CPU’s manufacturer.