PC won't post with XMP enabled

[Rinkzate]

Hey there folks - I've been ignoring this problem for a few months but would now really love to get my ram working at the speed I paid for.

Motherboard: Asus Z790 Maximus Hero - Bios 2301 (newest)

CPU: Intel i9-13900k

RAM: G.Skill F5-6400J3239G32GX2-TZ5RK (DDR5 2x32gb 6400 mt/s CL32-39-39-102 1.40V)

GPU: EVGA FTW3 Ultra RTX 3090TI

Prior to putting this computer together I checked the QVL for the motherboard and that ram is indeed listed on the QVL, so I'm really not sure why I can't get the computer to post with XMP or XMP II

I have tried standard steps such as swapping the sticks, changing the slots, and that has not helped at all so I am currently running them in A2 and B2 as recommended by Asus.

Under default "AUTO" setting I can post just fine... At 4000mhz, but with any XMP setting enabled my computer just flashes codes quickly (training I guess?) until it arrives at q code 55, and then just stays there indefinitely.

 

Please let me know if any other details are needed and I appreciate any assistance here, this has been driving me nuts.

[Tetras]

What's the highest manual frequency it will post at with XMP enabled?

 

You have two dual rank sticks there which will lower the headline speed somewhat compared to 2x16GB and I'm not sure what a 13900K is usually capable of.

[Rinkzate]

1 minute ago, Tetras said:

What's the highest manual frequency it will post at with XMP enabled?

 

You have two dual rank sticks there which will lower the headline speed somewhat compared to 2x16GB and I'm not sure what a 13900K is usually capable of.

Generally speaking, I'm not familiar with RAM tuning at all and have no understanding of any of the the many manual settings in my bios, so I've avoided doing anything manual like the plague so I don't actually know what it will post at other than the auto setting.

I'm a little confused, what I have is the kit shown at https://www.amazon.com/gp/product/B0BJ7X9P1W/ and since I bought them as a kit I figured that advertised speed would be what it would hit with xmp enabled. You're saying there's something about this kit though that prevents that because it's too much ram?

[Tetras]

1 minute ago, Rinkzate said:

You're saying there's something about this kit though that prevents that because it's too much ram?

Not the kit, the CPU.

 

Intel and AMD derate their CPU's memory controllers for 1. number of sticks and 2. the number of ranks per stick.

 

The more sticks and the more ranks, the lower frequency you get.

 

Intel's official spec for 13th gen K CPUs is 5600 for 2 sticks and 4400 for 4 sticks.

 

From what I'm aware of (watching overclocking videos), 13th and 14th gen K CPUs start to have problems when ran over 7200, but since you have 64GB I suspect that number might come down.

 

If your CPU runs fine with XMP enabled and a manual frequency of 6000 or 6200, for example, then your CPU's memory controller could just be saying "no", and/or you maybe need some more voltage.

[Rinkzate]

42 minutes ago, Tetras said:

If your CPU runs fine with XMP enabled and a manual frequency of 6000 or 6200, for example, then your CPU's memory controller could just be saying "no", and/or you maybe need some more voltage.

Gotcha, ok. I've been giving it a shot and so far I've had the same problem with both 6200 and 6000. I've been able to find quite a few people having similar problems by searching my ram kit model in quotes, but it seems like there is never really a solution unfortunately :/

[RONOTHAN##]

1 hour ago, Tetras said:

I'm not sure what a 13900K is usually capable of.

The good top out at 6800, the average top out at 6400, and the bad top out at about 6000, at least with auto settings. 

 

1 hour ago, Rinkzate said:

until it arrives at q code 55, and then just stays there indefinitely.

In my experience this is usually a timing issue, not a frequency issue (frequency will usually hit a 3-4 POST codes, go to 55, then restart, not sit there indefinitely), making it sound like it's not reading the XMP profile correctly. Try manually inputting the XMP settings while leaving XMP disabled, so manually set the frequency to 6000MT/s, set the timings to 32-39-39-102 for tCL-tRCD-tRP-tRAS (leave tRCDW on auto or set to the same as tRCD), and set the DRAM VDD and DRAM VDDQ setting to 1.4V. 

 

Also, just to make sure, are you mounting the RAM in slots 2 and 4 if you're counting from the CPU? If not, that can cause the issue you're experiencing. 

[Rinkzate]

2 minutes ago, RONOTHAN## said:

The good top out at 6800, the average top out at 6400, and the bad top out at about 6000, at least with auto settings. 

 

In my experience this is usually a timing issue, not a frequency issue, making it sound like it's not reading the XMP profile correctly. Try manually inputting the XMP settings, so manually set the frequency to 6000MT/s, set the timings to 32-39-39-102 for tCL-tRCD-tRP-tRAS (leave tRCDW on auto or set to the same as tRCD), and set the DRAM VDD and DRAM VDDQ setting to 1.4V. 

So interestingly enough - I had actually just gotten it to work via a suggestion I found buried in a forum online - setting dram timing to "mode 2" instead of auto. So my guess is that you are correct and it is the timings, but do you think I should just leave it on mode 2 or would what you suggested be more optimal (if it works)?

[RONOTHAN##]

1 minute ago, Rinkzate said:

So interestingly enough - I had actually just gotten it to work via a suggestion I found buried in a forum online - setting dram timing to "mode 2" instead of auto. So my guess is that you are correct and it is the timings, but do you think I should just leave it on mode 2 or would what you suggested be more optimal (if it works)?

OK, I'm trying to think of what setting you're referring to. Is it XMP II rather than XMP I? If not, can you take a photo of the setting and where it's located in the BIOS, just so I can get some context as to what it does? For reference, ASUS tends to call some of their BIOS settings weird names, so this could be either them loading a few "optimized" timings (what XMP I does vs. XMP II just loading everything on the sticks exactly), a different method of training the memory, a different ratio for the memory controller, etc., some of which are perfectly fine and some of which can completely destroy performance. 

 

Unless the setting is one that will destroy performance, as long as it's stable I'd be fine running it. I'd run a stability test or two just to make sure though, since this is a higher speed kit and the Intel memory controller is nothing if not inconsistent. 

[Rinkzate]

1 hour ago, RONOTHAN## said:

Is it XMP II rather than XMP I?

Nah, on the main "Extreme Tweaker" page I have a choice between XMP, XMP ii, and "Asus Tweaked" or something like that, but then in Extreme Tweaker>DRAM Timings> there's a drop down at the very top for "maximus tweak" and then there you have the choices of Mode 1 and Mode 2

It's shown on the right half of this image here

[RONOTHAN##]

1 hour ago, Rinkzate said:

Nah, on the main "Extreme Tweaker" page I have a choice between XMP, XMP ii, and "Asus Tweaked" or something like that, but then in Extreme Tweaker>DRAM Timings> there's a drop down at the very top for "maximus tweak" and then there you have the choices of Mode 1 and Mode 2

It's shown on the right half of this image here

OK, I know that setting. Maximus Tweak is just two different memory training modes, different CPUs prefer one over the other and it seems that yours much prefers mode 2. 

 

I would want to run some memory stress tests though to make sure it's stable, since in most cases if you have to resort to using those settings you're memory is right on the edge of stability. The one I have had the best luck with finding frequency related memory instability on 13th/14th gen is Y-Cruncher YT3, launch it by either hitting 1, 8, 18, 0 in that order, or by launching Y-cruncher in command prompt with the command "y-cruncher.exe stress VT3" optionally with the -TL:7200 flag to set it to run for 2 hours (change the 7200 to the number of seconds you want). I would want to run this for at least 2 hours to declare the frequency stable. If you want to test for timings, the one I've had the best luck with is TestMem5 with the 1usmus_v3 preset.