MAXIMUS VIII HERO will not boot when XMP is enabled for DDR4 3000 RAM

[Argonous]

Hello all,

I am putting together a new gaming build that involves the following:

Processor - Intel Core i7-7700K Kaby Lake Quad-Core 4.2 GHz
Motherboard - ASUS MAXIMUS VIII HERO
RAM - 32 GB (4 x 8GB) G.SKILL Ripjaws V Series DDR4 3000 (F4-3000C15Q-32GVRB)
Timing: 15-16-16-35, CAS Latency: 15, Voltage: 1.35V

When booting with the BIOS at the default setting, I only see 16 GB of RAM running at 2166. I know that I need to enable XMP to get the correct amount and speed, which I have done. However, when I do enable XMP and set the default RAM profile, it will no longer boot. I have to clear the CMOS just to get back into the BIOS.

Any suggestions on what to do next? I assume I should try to manually set the Timing, CAS, & Voltage, but I am clueless as to how to do so in the current ROG interface and I have yet to find a good guide.

Thanks in advance!

 

[MeanMachine41]

Hi Argonous

Although your MB supports OC RAM, your i7-7700K officially supports up to 2400Mhz. Yes your 3000MHz RAM may work at 2400Mhz but not their rated speed. As your RAM is not the rated JDEC standard then your XMP profiles may not be recognized. You will require manual input to Bios Primary Timings and Voltage. That is done in Bios under more Advanced settings in DRAM Timing control.
You can obtain your SPD info in Bios under the Tools tab and sometimes XMP works better after a Bios update. Settings located in Ai Overclock Tuner.

It is important to have your Bios updated to latest for better system stability and to address new RAM especially with DDR4. You should also check if your RAM has been tested with the MB and RAM Part No is verified on the QVL list. If not you take a risk.

Best way to update your Bios on the MAXIMUS VIII HERO is thru your rear IO panel. This way you don't need Windows or your Bios to update. If you need help then I can detail.

There are only general purpose guidelines as many systems are different. You just have to learn it as it is with all Overclocking.

 

[Argonous]

Thanks for replying Mean,

Updating the BIOS was one of the first things I did.

I was able to get it up to 2400Mhz without too much trouble, but it still only reads as 16GB although I have 32GB installed.

So, my next question is, would switching to 32GB of a Z270 compatible RAM such as G.Skill Trident Z make a difference?

Thanks again!

 

[MeanMachine41]

Yes we all want our RAM running at it's rated speed or better however you chose OC RAM.

Is it in Windows or Bios where it reads 16GB.?

Have you tried with just 16GB instead of 32GB and trying different RAM slots and switching modules.?
Could be dead DIMM slot or module not seated correctly. It's really best to consult with the MB QVL or you had better know your Bios if you intend to OC.

You may also wish to consider a Memtest86 on your modules to eliminate the possibility that there's a failing module.

Many different RAM types for Z270 MBs, As long as it's DDR4 then no harm trying.

I always choose my RAM kit based on the MB QVL that have been tested and have a decent chance.
It also comes down to the IMC (Integrated Memory Controller) for OC RAM. They all vary (CPUs) and the more RAM and higher the frequency then more strain on the IMC.

 

[Argonous]

It is only showing 16GB in both the BIOS and Windows 10. I am not too concerned with what Windows is showing just yet.

The QVL does show the 16GB version of the RAM (F4-3000C15Q-16GRR) as compatible, but also lists it as "16GB (4x4GB)"

I did reset the modules in different slots, but have not done a test on each individual module yet. I will give that a try along with Memtest86 tonight and see what happens.

Thanks Again!

 

[Argonous]

I tested each module individually and all seem to be good. However I was still unable to get the BIOS to show more than 16GB when all 4 were set... frustrating!

I decided to go ahead and switch out the MB to an ASUS ROG Maximus IX Hero to be inline with the Kaby Lake (Z270) chip and am considering exchanging the RAM for something that is more compatible with the Kaby Lake processor. Would it be worth it? If so, what manufacturer and part no. should I be looking at? I have had a bit of a tough time finding modules that specifically say they work with the Z270 chipset.

Thanks again!