Max XI F: BIOS 1902/1903 issues with XMP

[BizSAR]

After flashing BIOS 1902 or 1903 on my Maximus XI Formula, if I set it to utilize XMPI or II, the platform makes a number of attempts to boot, then boots into BIOS safe mode. I'm able to reproduce this even with all other BIOS settings at default.
Flashing back to 1802, I have no issues.
CPU: i9-9900KF
Memory: Crucial Ballistix Tactical Tracer RGB 3000 MHz, 4 x 8GB CL15 BLT8G4D30AET4K
Can provide more stats if needed.

[ionised]

Hey AndAbel,

Just wanted to chime in and say I'm having the same issues on my ROG Strix Z390-F.

Rock solid stable on BIOS 1802, POST failures on BIOS 1902, 1903 and 2004.

I learned that the issue (for me at least) is that every BIOS after 1802 has not liked me setting my DRAM frequency to anything higher than 2400Mhz. At 2400Mhz or lower it boots into Windows fine.

My RAM is rated higher though, and runs stable (and stress tested) at its rated speeds on BIOS 1802, which I'm sticking with until ASUS releases a fix. If they ever do (seems like months and sometimes a year or more between BIOS updates).

So yeah, your hardware absolutely isn't the problem. This issue was introduced in BIOS 1902 and has persisted through subsequent BIOS updates.


* EDIT *

Seems like the exact issue (for me at least) is that BIOS 1902, 1903 and 2004 all fail to POST with four DIMMS set to anything higher than 2400Mhz.

If I use two DIMMS, my rated speed (3000Mhz) is fine.

On 1802, four DIMMS works fine at rated speed as well.

The problem is in the BIOSs since 1902, and prevents running 4x DIMMs at higher than 2400Mhz.

Relevant post: https://rog.asus.com/forum/showthrea...064#post850064

[AndAbel]

Hey, just want to let everyone know that I've solved part of the problem I was having. I disabled the CSM with 1802 and it started getting stuck on white, but still booting, with the monitor coming on only when it got to the desktop, just like before with the old RAM on 1903. This happened with the new RAM on 1802 for the first time only after disabling the CSM. I realize now that I had disabled the CSM with 1903 on the old RAM as well, trying to get Rebar to work.

I figured out that the problem has to do with how long I wait after initially providing power to the PSU and mobo. With the CSM enabled I can push the front power button on my PC immediately after first supplying power to the board and it boots normally every time, but for some reason when the CSM is disabled I have to wait somewhere between 5-30 seconds before hitting the front power button or it gets stuck on white every time.

Thats why rebooting would sort out the problem, because it had already been supplied with power for much longer than 5-30 seconds.

I've tried this many times now with 1802 and have basically confirmed that if I wait the 5-30 seconds after first supplying power to the board before powering the machine on fully, it boots normally every time with the CSM disabled. If I power on the machine immediately after supplying power to the board without waiting the 5-30 seconds it gets stuck on white every time with the CSM disabled. If the CSM is enabled it will boot normally every time regardless of how quickly I power on after first giving power to the board through the PSU.

That said, this does not explain why 1903 will not post after a fresh install with this new RAM.

I still have not yet tried the latest BIOS myself.

[STARRAIN_ROG]

Hi ionised,
Do you mean on bios 1902, 1903 and 2004 with all four DIMMs, if you enable XMP to set the RAM frequency higher than 2400Mhz, the RAM and CPU qled on motherboard will flash and no boot?
If you clear cmos and with bios all default settings, the RAM frequency would be 2400Mhz, and the pc can boot into windows?
If you use DIMM_A2 and DIMM_B2, the pc can boot into windows with the rated speed (3000Mhz)?
May I have the following information?
- the serial number of the motherboard via PM
- the bios settings
- OS version and OS build
Thank you.

[AndAbel]

2004 posted with the new c14 RAM, although it took many more attempts than it used to after installing a new BIOS(I noticed this with 1903 and the old c16 RAM as well). Never the less, I have the CSM disabled with Rebar properly enabled finally and I'm booting normal every time now so long as I wait the 10-30 seconds after first switching on my surge protector power bar.