DRAM went unstable and cannot boot to bios after recent BIOS update

[MuchyCZ]

Hello. My pc components are
ROG Strix B450-F gaming
AMD Ryzen 5 2600
ROG Strix radeon RX570
Evga 500 BQ
Patriot Viper RGB Series 16GB KIT DDR4 2666Mhz CL15

I recently updated bios from the asus.com. I installed the Version 2301. I did it properly via flash usb disk drive and followed all the recomendation from Asus. All went good but after the update finished i cannot boot it up. It was all running, fans and so but no boot to bios. I was afraid i bricked the motherboard but ive tested it on another setup and it was working. I replaced the Dram for (G.SKILL 16GB KIT DDR4 3200MHz CL14 Flare X for AMD) and it suddenly boot up with it. I tested the previous Patriot RAMs on other pc setup and they are working aswell. The new G.SKILL modules, however, after enabling DOCP in bios to higher up the frequency did the same thing to the pc - it wont boot up. So i figured it out that hardware should be okay. I tested all modules and motherboard. Separately they works normally. The BIOS itself for some reason made the PC unstable in the matter of DRAM frequencies and reading.

This behaviour is weird to me and i dont know what to do with it now. Is it possible to downgrade bios? Should i wait for new BIOS version? I mean, the PC now works, but i have now, not very cheap, DRAM set to 2400MHZ and cannot do anything about it because it would make the mobo not read them at all. You guys have any experience with this issue? Sugestions? Thanks a lot.

[MeanMachine]

G.SKILL 16GB KIT DDR4 3200MHz CL14 Flare X for AMD is OC RAM and therefore D.O.C.P profile will not work as they exceed the JDEC standard.

If you check with CPUz in Windows (or the Tools section in Bios). you will find your RAM frequency has defaulted to 2400MHz and to get to their rated frequency will require manually entering their SPD values in Bios DRAM_Timing control. Note the SPD (Serial Presence Detect) values and voltage of your RAM and make the adjustments accordingly.
If you have no success then try lower timings or increase DRAM voltage in +.05V steps and see if that helps stability.

[MuchyCZ]

G.SKILL 16GB KIT DDR4 3200MHz CL14 Flare X for AMD is OC RAM and therefore D.O.C.P profile will not work as they exceed the JDEC standard.

If you check with CPUz in Windows (or the Tools section in Bios). you will find your RAM frequency has defaulted to 2400MHz and to get to their rated frequency will require manually entering their SPD values in Bios DRAM_Timing control. Note the SPD (Serial Presence Detect) values and voltage of your RAM and make the adjustments accordingly.
If you have no success then try lower timings or increase DRAM voltage in +.05V steps and see if that helps stability.

Thanks for the answer. Il try that asap.

[Rockford]

!slightly overcourse but!

with the newer bios updates, the memory speed cant be set high at first go 2400mhz-3200mhz (example), it will result in failed post, orange light hang

What i have to do to reach 3466mhz, is to use no more than 300mhz increasements from 2400mhz--> 3466mhz

2400mhz (set 2666mhz)
reboot
2666mhz (set 2933mhz)
and so on
eventually 3466mhz stable

note that this is with my memory kit in particular

With the good old 1003 bios (b450i), when i bump memory speed up from 2400mhz-3466mhz at once it sometimes failed bios post at first try (red light), but just save and exit in bios and the second try works flawless (timing and frequency is now stuck and stable)
But this dont work with the new bios versions, no bone for this watchdog...




Set the trident XMP 3200mhz profile in bios and manually set dram voltage to 1,35v, but lower the frequency to only 2666mhz at first boot, then increase frequency gradually (text above)

Default TCWL (tertiary cas write latency timing) this setting can cause issues with memory speeds, performance and stability also (depending on which bios and cpu is being used)

Good luck and keep on tinkering, its often a matter of how to get it to work ))