DDR4 memory modules are available at a stock frequency of 2133MHz, but memory vendors encode XMP profiles which can automatically modify the frequency and timings of the supported memory modules to work in par with your CPU. With the X99 Series, GIGABYTE is offering a tested and proven platform that ensures proper compatibility with profiles up to 3400MHz.
What is XMP?
The synchronization of the memory modules
with the CPU is crucial for good performance of your system. DDR4 memory
modules are available at a stock frequency of 2133MHz, but as frequency
tweaking requires a considerable amount of effort and knowledge, memory
vendors encode XMP profiles which can automatically modify the timings
of the supported memory modules to work with your CPU and to achieve
increased performance.
* XMP Profile support may vary depending on memory module.
Please refer "Memory Support List" for more information.