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megafettarsch · ‎05-23-2016

Hello guys,

i built a new gaming computer with:
- maximus viii hero
- i7-6700k
- G.Skill Trident Z 16GB DDR4 16GTZ Kit 3600 CL17

i just started everyhing up and installed windows (so far no problems). later on i decided to start making some adjustments in the bios. first thing was loading
the xmp profile for the ram. the computer didn't boot up. even in manual mode i couldnt raise the ram frequency to 3600. ( remember: everything else unchanged).
i left it with this try and moved on to the cpu. i overclocked the cpu quite successfully (so at least something is working correctly). later on i tried loading the ram xmp profile again with no success.

i started to examine the problem further and ended with the discovery: i just simply can't raise the default ram voltage over 1.2V. Even one increment above leads to boot-failure-loop. The computer
gets powered on, the QCode display shows some numbers and ends with the number 41 ( no hint in the manual) and the red led is lighting up. i can reduce ram voltage though.
so i guess the problem with xmp can be a problem with the ramvoltage (since xmp wants to change it to 1.35V (which i discovered can't be achieved)).

i tried bios 1701 and 1401. on top i cleared it with the cmos button. i checked my ram sticks in every slot alone and together. i even tried the ram from my friend ( he has the exact same), no success.
everything is working normal when i start the pc with the default ram settings (2133mhz and 1.2v). but i am quite disapointed because i bought a much faster and expensive ram. And i am curious if something
on the motherboard is just defect? or can it be the cpu (cause the red led is lighting up (which stands for cpu)).

i never installed any asus software in windows (read about some problems and i wanted to oc in bios anyways). what i did was i once used the TPU function in bios(which would tune some settings). could it be possible, that
this lead to a malfunction in the bios since there seems to be a limiter in the ram voltage.

i dont know what to do further, since i feel like i am doing everything right.
hope someone can help and maybe others with xmp problems can try raising their ram voltages (i saw a lot of ppl with xmp problems)

thx in advance

Chino · ‎05-23-2016

Are you sure you're modifying the correct voltage?

megafettarsch · ‎05-24-2016

Chino wrote:
Are you sure you're modifying the correct voltage?

Hey,

yes i am sure. It's the voltage which gets altered to 1.35V when loading the xmp profile. And i can lower it (as described) and read it out in windows.

I even tried playing with the V_ccio and V_sa to "support" the process of raising the voltage of the ram.

The ram i am using is not listed in the manual of the motherboard in the Qualified vendor list (ram of the same producer and even of the same series (with less frequency) are though).
I think a Bios update in the past raised the maximum ram frequency the board is capable to run. Still this exact Ram is NOT listed in the QVL. So, can this cause the Error?

I would think i should still be able to raise the voltage over 1.2V (even the tiniest bit), but maybe i am wrong and the "wrong" ram shuts down this process immediately.

What do you think?

edit:
didnt saw the "new" QVL for ram. https://www.asus.com/de/Motherboards/MAXIMUS-VIII-HERO/HelpDesk_QVL/

i own the F4-3600C17D-16GTZ (2x8Gb), which is actually still not a member of the qvl (his 4x4Gb "brother" is still in though). question remains the same: could this cause the error?
i dont know if i need to get/swap/rma the cpu, ram or motherboard ;/

Chino · ‎05-24-2016

I've tested practically all of the BIOS that were released. I never found any issues with increasing DRAM voltage. Running DDR4 3600 probably requires manual tweaking. You stated that you've tried tweaking the IO and SA voltages. How high have you gone on each voltage?

Also are you using the DIMM_A2 and DIMM_B2 slots for your memory modules?

megafettarsch · ‎05-24-2016

Chino wrote:
I've tested practically all of the BIOS that were released. I never found any issues with increasing DRAM voltage. Running DDR4 3600 probably requires manual tweaking. You stated that you've tried tweaking the IO and SA voltages. How high have you gone on each voltage?

Went to up to 1.25V each. Yes i am aware that 3600 is quite high (even if its speicfied for the mainboard), so i started to track down the error (as stated).
I cleared cmos (so everything is default; ram frequency == 2133 Mhz) and i just changed DRAM Voltage from Auto to:
1.205V -> Not booting (with failure q code 41 and red led showing up in the end)
changed it back to 1.2 V -> booting
changed it to 1.995 V -> booting
so in my opinion, the imc is not working correctly. to go further: xmp wants to change DRAM Voltage to 1.35 (which will not boot), and so xmp is not working either

Chino wrote:
Also are you using the DIMM_A2 and DIMM_B2 slots for your memory modules?

Yes, i even tested both sticks on their own in every slot.

i chatted with asus support in the last hour and the support guy (i was supprised he was quite competend, he really took his time to help me out) and i came to the decision that its a malefunction from my particular motherboard.
we did a nice photo session to proof the cpu and the socket on the mb is not defect. so there are only 2 options left in my opinion:
cpu defect (cause IMC is integrated)
ooor motherboard defect. i will test my cpu in my friends computer, but i guess its the mainboard. mhmhm

can't raise ramvoltage over 1.2 V ( hero) any limiter? xmp not working cause of that?