Maximus XI Hero and G.Skill 4133 Mhz Cl19 booting problem

[Ch1re]

Hello,

I have a problem with: Maximus XI Hero (Wi-Fi) + 9900k + G.Skill 4133 Mhz Cl19 (F4-4133C19D-16GTZR - listed on the QVL) combo.
With enabled XMP, it's almost impossible to pass the booting process - 9 out of 10 attempts ends with POST code 23.
However, in rare cases when it has passed booting process computer was 100% stable - also booting problem doesn't exist when I disable one of the RAM channel by BIOS which makes that RAM working in single channel mode.

It seems that the memory training is not able to handle that RAM even though it is listed on the QVL.

BIOS: 0602

[mdzcpa]

I can get my Gskill Trident Z 4133 17Q to boot and run stable at 4133 using XP1 on my Hero XI. Above that I can get it to run, but it requires manual tuning. So it's definitely not the motherboard. It really comes down the CPU's IMC, your cooling and how hard you push the CPU clocks.

I am still surprised how many folks buy expensive top end highly bin clocked RAM thinking it will run just because the board supports it and fail to even consider the CPU's memory controller. We've been dealing with internal memory controllers on CPUs for quite a few years now. I suppose it would be helpful if board makers and RAM kit sellers really underscored that point on their advertising material. Might save some heartache (and likely reduce some sales) . A lot of folks drop big cash on high end binned RAM that they cannot run with a weaker IMC on the CPU.

[HiVizMan]

mdzcpa wrote:
I can get my Gskill Trident Z 4133 17Q to boot and run stable at 4133 using XP1 on my Hero XI. Above that I can get it to run, but it requires manual tuning. So it's definitely not the motherboard. It really comes down the CPU's IMC, your cooling and how hard you push the CPU clocks.

I am still surprised how many folks buy expensive top end highly bin clocked RAM thinking it will run just because the board supports it and fail to even consider the CPU's memory controller. We've been dealing with internal memory controllers on CPUs for quite a few years now. I suppose it would be helpful if board makers and RAM kit sellers really underscored that point on their advertising material. Might save some heartache (and likely reduce some sales) . A lot of folks drop big cash on high end binned RAM that they cannot run with a weaker IMC on the CPU.

Never a truer word been spoken in some time my friend. I can not stress just how important the IMC of a cpu is. Folks are so used to discussions about a 'good' cpu being one that will do a frequency at a silly low voltage but that is just one part of what the current CPU is all about. IMC is as critical if not more so in todays memory hungry and dependant software.

Great post mate.

[vinceX]

I'm having the same issues on the latest BIOS, I'm using 2 * F4-4000C19-16GTZR (64GB) manually tuned at 3600mhz CL16. The BIOS won't post sometimes, but after a few attempts it'll work fine. The memory works also fine in Windows and passes 8h of memtest.

[Silent_Scone]

vinceX wrote:
I'm having the same issues on the latest BIOS, I'm using 2 * F4-4000C19-16GTZR (64GB) manually tuned at 3600mhz CL16. The BIOS won't post sometimes, but after a few attempts it'll work fine. The memory works also fine in Windows and passes 8h of memtest.

The memory isn't fully stable and is failing POST stress tests. Normally, this can be dialed out by tuning the VCCIO and VCCSA voltages. Alternatively, relax tRCD by one clock

[vinceX]

Silent Scone@ASUS wrote:
The memory isn't fully stable and is failing POST stress tests. Normally, this can be dialed out by tuning the VCCIO and VCCSA voltages. Alternatively, relax tRCD by one clock

Thanks for the suggestion, I tried the steps but I had to dial down the memory clock to 3200mhz, which is unfortunate. To make it run at higher speed I had to enable fast boot both in Boot settings and RAM's MRC. Is there any way for anyone on your side to test these sticks?

[Silent_Scone]

vinceX wrote:
Thanks for the suggestion, I tried the steps but I had to dial down the memory clock to 3200mhz, which is unfortunate. To make it run at higher speed I had to enable fast boot both in Boot settings and RAM's MRC. Is there any way for anyone on your side to test these sticks?

That's one of the many reasons it's not recommended to mix memory. Vendors bin these kits at the density they are sold in. The higher up the frequency spectrum you go, the less likely it is that mixing kits will work. 4000/4133MHz at that density would not only require a very good IMC, but a singular kit, too.

[vinceX]

Silent Scone@ASUS wrote:
That's one of the many reasons it's not recommended to mix memory. Vendors bin these kits at the density they are sold in. The higher up the frequency spectrum you go, the less likely it is that mixing kits will work. 4000/4133MHz at that density would not only require a very good IMC, but a singular kit, too.

Makes sense. The kit I have is from the same batch and has all consecutive SN. The main reason I got 2 pair of a 32GB Kit is that I cannot find any G.Skill 4000mhz CL19 RGB Kit for 64GB.

[Aurosonic]

A got some memory issues with my Formula XI as well. Memory kit G.Skill F4-4266C17Q-32GTZR
Wasn't able to pass stresstests at 4266CL17 no matter which vccio and vccsa, tried up to 1.4v
Been able to pass tests by downclocking it to 4200. After 3 month of successfull usage at one day my system hang so even reset didn't work.
I turned off the system and on next boot i got postcode CC. None CMOS reset, retry, memok didn't help to pass this CC postcode.
Then i've tried to check each memory stick separately and found that 1 of the sticks caused the problem. I've tried it in each of four slots and it gave me postcode CC every time.
Once i remove this stick and leave three others, system boots perfectly fine but i had to downclock it to 4100 to make it work stable (seems like cuz of T-Topology).
Tomorrow i'm gonna sent memory back by warranty.

Got another kit, 2x8 this time F4-4600C18D-16GTZR. Same as previous kit it works stable only at 4100CL17 due to T-Topology. Now i've ordered APEX XI Motherboard and hopefully it'll solve all my issues and i could run at least 4400CL17 stable with my F4-4600C18D-16GTZR kit.

[Silent_Scone]

I will grab one of the validated 4 DIMM kits @ 4266 if I can and will test. It can often come down to CPU IMC strength when going beyond 4K.

[Aurosonic]

Silent Scone@ASUS wrote:
I will grab one of the validated 4 DIMM kits @ 4266 if I can and will test. It can often come down to CPU IMC strength when going beyond 4K.

I'll wait till APEX XI come and test my CPU with new memory kit, so it will be evident if it was motherboard or cpu imc issue. Then i'm gonna change my kit to 2x16 4000CL19 and will OC it to 4133CL17. One of my friends got this kit on Gene XI and it works perfectly.