ASRock Forums : X370 Gaming K4 Mem Help

parsec wrote:

... the DDR4 XMP profile data for Intel X99 processor memory controllers won't work with the Ryzen memory controller. The memory controllers are different, and some of the memory settings are different. When using DDR4 memory designed for other systems with a Ryzen system, the memory timings must be set manually.

How can the Ryzen memory controller, a piece of hardware that is part of the CPU, be changed by a UEFI/BIOS update to support the XMP data/settings for the memory controller of Intel Haswell-E and Broadwell-E processors? The good news is at least your Corsair memory will work with a Ryzen system.

All modern memory also contains multiple sets of basic timing data for different non-over clocked supported speeds of a model of memory. That data is referred to as the JEDEC or SPD data, which you can view in the CPU-Z SPD tab. One set of that data is the memory timing data used for the default speed of your memory, most likely 2133. The SPD data allows a mother board's UEFI/BIOS to automatically set the timing parameters for our memory.

XMP data is simply another convenience for setting memory timings to the correct values for the "EXtreme Memory Performance" speed of memory. That is the over clocked speed of your memory, which is any speed beyond the specifications of the memory controller in your CPU. Unfortunately, we've become used to using it, and the memory manufactures don't provide any other information about the timing settings for their products.

If you cannot set memory parameters manually, you'll simply need to wait for Ryzen specific memory to be available. Of course a valid question is, what are the correct timing settings to be used with the Ryzen memory controller with your model of memory?

That is something that Corsair should provide for you. If they tell you to use the XMP profile, you know that does not work, and is a wrong answer. If they tell you to wait for mother board BIOS support, they are putting you off, and just hoping the mother board manufacture will do their work for them.

Here are some example timings for your memory that was CPU-Z verified on a good sized set of Ryzen boards. Note that setting the Command Rate (CR) to 1T is needed for achieving higher speeds, which is something that will never be found in DDR4 XMP data for Intel processors. Also note, reaching 3200 is very rare (so far), and if you are at 2666 now, you are above average.

http://rymem.vraith.com/detailed_ram/715