Question Does XMP allow to run higher RAM frequency than CPU officially supports?

[ulverbeast]

Hi all

I have been trying to research this topic for some days now but I feel like the information I get is very conflicting. I am looking at some DDR5 5600 MHz RAM for a motherboard that supports up to 5600 and higher. However, the CPU (i5 13400) according to Intels page only supports up to 4800 MHz (link).

So my question is whether XMP allows the CPU to run with higher than 4800 MHz RAM, or whether XMP only allows the RAM to run at advertised speeds on a CPU that supports them? I did a lot of googling but it's 50/50 which answer I get (link 1, link 2).

So, in essence: will XMP allow me to get the full 5600 MT/s out of my RAM on a i5-13400 which only officially supports up to 4800 MT/s?

 

[boju]

It's not the cpu that governs ram speed, well kind of within reason, it's whatever the board supports. B and Z chipset boards allow faster ram above CPU's memory controller.

 

[hotaru.hino]

I'd argue when the memory speed exceeds what the processor is officially capable of supporting, then the memory controller in the CPU may not actually be running 1:1 with the memory. For instance, the memory controller in most Zen 3 processors can go up to 3600MHz, but they're technically compatible with faster RAM. However, it does this by operating at different ratio than the memory, causing additional latency. Intel also has a similar concept they call Gears.

So I don't think when using memory that runs faster than the officially specified speed, the memory controller is actually running at that speed in a lot of cases.