Fatality X99X Killer 3.1, Memory Problems

NYURDRMS1 wrote: I am trying to use a matched set of 32GB G.Skill Ripjaws, 4x8GB 2800 memory. When I check the bios, I only see channel A and D showing that there is memory in the slot.  However when I check the HW browser, it shows a pic of the MB and shows that there is memory in the slots B and C, but for some reason they are not showing on the motherboard.  I have Bios 3.2 installed.  The timings on the XMP profile show DDR4 - 2800 16-16-16-36 1.20v However, when I check the browser on the memory it shows the memory is listed at DDR4 - 2133 15-15-15-36. I have the tried moving the sticks around, but have had no success.  So it doesn't seem to be the memory as the problem, other than it seems to list lower than what the MB is recognizing. I have any fast boot or energy saver turned off.  The MB can see the memory is in the slot, as it shows in the browser, but it doesn't seem to want to recognize it. Any help would be appreciated. Thanks, Chad

First, the full model number of your memory is required before we can check compatibility.

Next, the Intel guaranteed maximum memory speed for a Haswell-E processor is 2133, and for Broadwell-E, it is 2400. Any speed above those speeds with either CPU is a memory OC, and not guaranteed. The memory controller (IMC) is part of the CPU, so most of the responsibility for the maximum memory speed belongs to the CPU.

No idea what CPU you are using.

On the X99 platform, memory over clocks above 2600 are more difficult than below 2600. Above or even at 2666 on X99, the memory divider or BCLK rate is usually set to 125MHz, instead of the normal 100MHz. That also affect the CPU speed, and the core multipliers must be compensated for the increased BCLK speed.

Memory over clocks are not guaranteed, even by the memory manufactures. Just because you bought DDR4 2800 memory, does not mean it is guaranteed it work at that speed with your CPU and board, sorry to say.

Besides an increase of DRAM voltage to at least 1.35V, the VCCIO and VCCSA voltages also must be adjusted. That does not just mean increased. VCCSA in particular must be tuned to a certain value for the memory you are using and the quality of the IMC in your processor. What is the correct value? You must find it. But again, adjusting those voltages, and increasing the DRAM voltage beyond 1.35V, does not guarantee your memory will work at 2800.

The System Browser program is reading the default SPD data for your memory. Its default speed and timings are 2133, and 15-15-15-36. If you run CPU-Z, and click on the SPD tab, you'll see the default speed and timings for your memory, as well as the main XMP profile, which is just a special set of the SPD data that all memory has since at least DDR2.

The more memory you are trying to use, meaning total capacity (ie, 32GB), the more difficult it is to have it operate at high over clocks.

I also have seen the "disappearing memory" situation when over clocking my DDR4 memory on my ASRock X99 board. So far, I only have the memory in the B1 slot that is no longer recognized. When that happens, I know I am either at the limits of my memory OC with that memory, or I have work to do to try to get it to work.

What you can try:

You should be using the A1, B1, etc slots first, not the A2, B2, etc slots.

Do not use the XMP profile. Set everything manually, or use the DRAM Tweaker option in the DRAM configuration menu. But do that after the following step first.

Set ALL of the timing settings to Auto at first. See what the timings are if all the memory is recognized at the memory OC. You can then try to reduce the timings from there.

In the DRAM Configuration screen, at the bottom, set MRC Fast Boot to Disabled. Set Memory Training to Enabled, if you have that option. That will slow down POST, but allows higher memory OCs to happen.

Adjust VCCSA and VCCIO. Don't raise them to high. The maximum values are different between X99 and Skylake system, X99 having lower maximum voltages for those settings.

Increase DRAM voltage beyond 1.35V.

Did you try any of the memory OC preset settings that are probably available in the latest UEFI for your board? As I said above, at 2600 or above, these presets use a BCLK of 125 MHz, which affects the CPU speed, even with stock core multipliers. You will need to adjust the core multipliers to lower values in order to try the 125 MHz BCLK memory settings.

Frankly, I have lost a memory over clock with the latest UEFI version for my ASRock X99 board, that worked with an earlier version. I cannot use the same speed and timings with the newest UEFI version, that I did with an earlier version. Why that is, I don't know. I have not experimented enough with the new memory OC presets yet to see if I can use them successfully.

Just like a CPU over clock, memory over clocks are not guaranteed, and take work to get them operating and stable. There is no set "recipe" for any type of over clock. We also cannot expect to get as high a memory OC on the X99 platform than is possible on the new Skylake platform.