XMP not working

[Yahia Mohamed]

Just built my new PC the main specs to know are:

Corsair vengeance rgb pro DDR5 2X16 CL3 with SKU: CMH32GXM2B5600C36

ROG STRIX B660-A motherboard link: https://rog.asus.com/motherboards/rog-strix/rog-strix-b660-a-gaming-wifi-model/

and an I7-13700k

My problem is that when choosing XMP 1 or XMP 2, my PC does not post. I now know that my motherboard isn't compatible with my memory kit,  but is there some sort of way to make a custom overclock so that the memory kit can reach 5600 Mhz?

I also literally know nothing about ram overclocking

[Applefreak]

12 minutes ago, Yahia Mohamed said:

Just built my new PC the main specs to know are:

Corsair vengeance rgb pro DDR5 2X16 CL3 with SKU: CMH32GXM2B5600C36

ROG STRIX B660-A motherboard link: https://rog.asus.com/motherboards/rog-strix/rog-strix-b660-a-gaming-wifi-model/

and an I7-13700k

My problem is that when choosing XMP 1 or XMP 2, my PC does not post. I now know that my motherboard isn't compatible with my memory kit,  but is there some sort of way to make a custom overclock so that the memory kit can reach 5600 Mhz?

I also literally know nothing about ram overclocking

Are you running the latest BIOS?

[Tristerin]

Is your MB updated to the latest BIOS - each bios revision updates the QVL quite a bit.  If you are on an old BIOS revision it may fix the issue for you.

 

Secondly, are the sticks in the 2nd and 4th slot away from the CPU (the main slots for 2 sticks and can maintain the best speeds)

[RONOTHAN##]

First things first, just to make sure, are you running the RAM in slots 2 and 4 if you're counting from the CPU side? Because of how DDR5 memory topologies are setup and how ridiculously high speed DDR5 is, those are the two spots that need to be populated first in order for the system to have a shot at running higher memory speeds. 

 

If you confirm they're in the right slots and XMP still doesn't work, try manually entering the memory settings. Find the voltage and enter that where it says "DRAM Voltage" or whatever ASUS calls it (maybe DRAM VDD), enter the frequency, and see if it boots. If it does, go back and enter the timings, then run a memory stress test. If you can't get it to boot, try raising the voltage (up to 1.4V should be fine without active cooling), and if that doesn't help start slowly walking down the memory frequency till it can post. 

[Yahia Mohamed]

7 hours ago, Applefreak said:

Are you running the latest BIOS?

Yeah

[Yahia Mohamed]

7 hours ago, RONOTHAN## said:

First things first, just to make sure, are you running the RAM in slots 2 and 4 if you're counting from the CPU side? Because of how DDR5 memory topologies are setup and how ridiculously high speed DDR5 is, those are the two spots that need to be populated first in order for the system to have a shot at running higher memory speeds. 

 

If you confirm they're in the right slots and XMP still doesn't work, try manually entering the memory settings. Find the voltage and enter that where it says "DRAM Voltage" or whatever ASUS calls it (maybe DRAM VDD), enter the frequency, and see if it boots. If it does, go back and enter the timings, then run a memory stress test. If you can't get it to boot, try raising the voltage (up to 1.4V should be fine without active cooling), and if that doesn't help start slowly walking down the memory frequency till it can post. 

Tried all of that, the only frequency my pc can safely post in is 4266 MHz

[RONOTHAN##]

12 minutes ago, Yahia Mohamed said:

Tried all of that, the only frequency my pc can safely post in is 4266 MHz

That really sounds like it's in the wrong memory slots, or the BIOS is broken. If you have confirmed that it's in slots A2 and B2 on the motherboard, I'd try a couple different BIOS updates for 13th gen as well as reseating the RAM and CPU to see if that can get it to POST at a higher speed. 

[Yahia Mohamed]

55 minutes ago, RONOTHAN## said:

That really sounds like it's in the wrong memory slots, or the BIOS is broken. If you have confirmed that it's in slots A2 and B2 on the motherboard, I'd try a couple different BIOS updates for 13th gen as well as reseating the RAM and CPU to see if that can get it to POST at a higher speed. 

Unfortunately, the current version of BIOS am running is the only one that supports 13th gen intel CPUs + this version does not support rolling back the bios.

[Yahia Mohamed]

On 11/17/2022 at 8:54 PM, RONOTHAN## said:

First things first, just to make sure, are you running the RAM in slots 2 and 4 if you're counting from the CPU side? Because of how DDR5 memory topologies are setup and how ridiculously high speed DDR5 is, those are the two spots that need to be populated first in order for the system to have a shot at running higher memory speeds. 

 

If you confirm they're in the right slots and XMP still doesn't work, try manually entering the memory settings. Find the voltage and enter that where it says "DRAM Voltage" or whatever ASUS calls it (maybe DRAM VDD), enter the frequency, and see if it boots. If it does, go back and enter the timings, then run a memory stress test. If you can't get it to boot, try raising the voltage (up to 1.4V should be fine without active cooling), and if that doesn't help start slowly walking down the memory frequency till it can post. 

I managed to reach a solution. I enabled XMP but instead of letting the memory run at 1.25V, I used 1.2 and the computer posted normally. Currently seeing the how much further I can go.

(EDIT) I couldn't reach anything higher than 1.2 not even 1.205. Stress tested the memory for a bit and everything was alright!

[Guest]

TLDR AT BOTTOM

 

hmm....you got better stability with higher ram speed using LESS voltage? 1.2 instead of 1.25?

 

Does anyone know if this is common for ddr5? I thought that normally with any RAM, you normally have to RAISE the dram voltage if anything?

 

I had heard that some other "related" voltages do have a sweet spot, so you don't want to raise them too high (I think system agent and memory controller both are like this?).

 

I have a 6400-32-39-39-102 SkHynix 2x16gb kit from G.Skill that I've been unable to get stable above 5800 on my MSI pro z690-a Wi-Fi ddr5 board with 12700k CPU.....

 

Tried many different things, but haven't actually thought to REDUCE dram voltage.

 

I do heard different things depending on who/where you ask. Some people say that on that setup, with SkHynix ddr5, should be able to easily do 6000 at least, probably 6200, possibly 6400 but that's probably pushing it. Other people say that in order to get anywhere even above 5600, you really need a 2 dimm only board, so the fact that I have 5800 running stable is extremely good, especially for 32gb of ram.

 

In all honesty, the performance difference in games seems basically non existent between 4800-39-39-39-77 and 5800-36-36-36-28 with custom sub timings, so I'm pretty much decided that I may as well just keep everything on auto and let the dram run at lower voltage 1.1V.

 

Benchmarks like aida64 do show big improvements to write/read/copy/latency results (around 20kMB/s for each and reduction of around 20-25ns latency), 3dmark shows improvement to CPU score.....but none of this really translates to improved fps in real world gaming situations.

 

XMP sets the kit at 1.4V, but with this, or even slightly higher, just can't get it stable above 5800 (unless I disable e-cores, but then CPU temps in general go through the roof).

 

Memory TryIt! has a profile for 5800-36-36-36-77 which it sets to 1.35V.

 

with 1.35V I can run 5800-36-36-36-28 + sub timings from BuildZoid, totally stable.

 

with 1.4V I can run 5800-30-37-37-28 + sub timings from BZ, totally stable.

 

I did try running this at 1.35V, but at this voltage for some reason, 36-36-36-28 performed better in aida64 than 30-37-37-28, or even 30-35-35-28.....so tightening the timings was still stable, but performed WORSE?

For this reason, I have the option to either stick with 5800-36-36-36-28@1.35V, temps are all fine, 100% stable......or just keep everything auto, since the actual performance in game is the same either way lol.

 

TLDR:-

 

-OP REDUCED dram voltage to improve stability, is this common for ddr5?

-any reason why tightening timings would ever still be stable, but produce WORSE performance in aida64?

- side note for anyone wondering, at least in my experience, real world gaming performance is basically the same between stock and OC RAM settings.