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AM5 boot times improve RADICALLY with memory context restore enabled

@GerKNG is your B650E steel legend having memory context enabled by default?

I just checked and in my BIOS it actually is enabled by default... that's why my boot times are most instantaneous... huh strange, if it causes so many problems, why would AsRock have it on by default? (stock bios when I looked)
enabled by default and i never had any issues with it.
it just works (except with manual overclocking)
 
I am now concerned to update my BIOS (mostly because of the beta bios's rolling for the 9000 series chips)

I think I need to though (my SSD is still showing as a usb/unpluggable in windows)
 
It's absolutely shocking am5 was released in this state and the long boot times are still going on. Surely there was a better design solution with memory training?
For the record: two option -

Memory Context Restore (MCR) -> One training and after the result loaded each start
DRAM PowerDown Disable -> you got minus (means better) 1-1.5ns latency in Aida64 memory benchmark.

You cannot use both, because it's can cause hard boot loop or even Windows file loss.
Several firm (like AsRock or MSI) use the MCR enabled by default.
Several other (like ASUS) use the MCR disabled by default.

The background is simple: in the early times there is a Youtuber named BuildZoid (actually hardcore overclocking) and he's guide mentioned the PowerDown disable settings.
Not one and not two person experienced then boot loop or even corrupted Windows files because of this settings used the MCR enabled setting.
The ASUS for example changed the UEFI after that and if you enable the MCR, the PowerDown Enabled (yea, this is the name) jumped disable and vica versa...

I actually use the MCR enabled and Powerdown disable with severe memory tuning (DDR5-6000 CL36 1.35V -> CL28 1.4V) without any issue:
 

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I actually use the MCR enabled and Powerdown disable with severe memory tuning (DDR5-6000 CL36 1.35V -> CL28 1.4V) without any issue:

you got me kind of tempted to do 1.4v and cl28 now, those are only the only two changes I have to make? i just enable EXPO, reboot, then change to 1.40v and the first 36 to 28 and reboot and done? do all the ram tests to make sure its good with no errors, but thats it?

leave everything else stock? my ram is the teamgroup t-power create ram 6000 (in my specs)

this is my ram: its fully stable with expo, i already ran several ram tests

1715752310782.png
 
you got me kind of tempted to do 1.4v and cl28 now, those are only the only two changes I have to make? i just enable EXPO, reboot, then change to 1.40v and the first 36 to 28 and reboot and done? do all the ram tests to make sure its good with no errors, but thats it?

leave everything else stock? my ram is the teamgroup t-power create ram 6000 (in my specs)

this is my ram: its fully stable with expo, i already ran several ram tests

View attachment 347459

The RAM tuning a bit tricky in AM5 / DDR5...
I suggest you first check your RAM kit at the HWinfo64 memory menu.

The best DRAM kits are made with SK Hynix A-Die, then M-Die.
Then follow a big dip with Samsung B-Die & Micron REV A / REV G.
Another big dip the Samsung D-Die.
The Micron REV B is anti-tuning as far as I know.

If you have A-Die or M-Die, then you can try it.
Foreword: DDR5 RAM settings calculator - make a local copy and you can explore it

Suggestion (and as always: I cannot guarantee anything and can't take any responsibility, just try to help with my personal experience):

-VDD and VDDQ raised to 1.4V
-Timings:
tCL 28
tRCD 36
tRP 36
tRAS 48
tRC 84

The other big thing is the tREFI (Resfresh Rate in ASUS) which can be 49151 or 65535 (the latter is the upper limit az AM5)
The other big thing is the tRFC, this is a hard one, highly depending of the DRAM type:

Hynix A-die DDR5-6000
tRFC: 416

Hynix M-die DDR5-6000
tRFC: 510

Samsung B-Die, Micron REV A, REV G DDR5-6000
tRFC: 832

Samsung D-Die DDR5-6000
tRFC: 864

And if you try anything, first test for a longer period (half a hour minimum) with Aida64 stress test, y-cruncher, TM5 or so.
If you change anything in you UEFI memory settings after the reboot there is a new memory traning phase starting, means longer period of black screen before POST screen.
Be patient and remain calm. :)
If the black screen remain after 4-5 minutes, do a BIOS reset and step back about the changes you made (ie.: if the tRFC 416 wont boot, then try 436 and so on).
 
The RAM tuning a bit tricky in AM5 / DDR5...
I suggest you first check your RAM kit at the HWinfo64 memory menu.

The best DRAM kits are made with SK Hynix A-Die, then M-Die.
Then follow a big dip with Samsung B-Die & Micron REV A / REV G.
Another big dip the Samsung D-Die.
The Micron REV B is anti-tuning as far as I know.

If you have A-Die or M-Die, then you can try it.
Foreword: DDR5 RAM settings calculator - make a local copy and you can explore it

Suggestion (and as always: I cannot guarantee anything and can't take any responsibility, just try to help with my personal experience):

-VDD and VDDQ raised to 1.4V
-Timings:
tCL 28
tRCD 36
tRP 36
tRAS 48
tRC 84

The other big thing is the tREFI (Resfresh Rate in ASUS) which can be 49151 or 65535 (the latter is the upper limit az AM5)
The other big thing is the tRFC, this is a hard one, highly depending of the DRAM type:

Hynix A-die DDR5-6000
tRFC: 416

Hynix M-die DDR5-6000
tRFC: 510

Samsung B-Die, Micron REV A, REV G DDR5-6000
tRFC: 832

Samsung D-Die DDR5-6000
tRFC: 864

And if you try anything, first test for a longer period (half a hour minimum) with Aida64 stress test, y-cruncher, TM5 or so.
If you change anything in you UEFI memory settings after the reboot there is a new memory traning phase starting, means longer period of black screen before POST screen.
Be patient and remain calm. :)
If the black screen remain after 4-5 minutes, do a BIOS reset and step back about the changes you made (ie.: if the tRFC 416 wont boot, then try 436 and so on).

I'm pretty sure I read somewhere mine is M-Die, if I get bored tomorrow I will give this a go and run the ram tests, thanks for your detailed help, very much appreciated.
 
The RAM tuning a bit tricky in AM5 / DDR5...
I suggest you first check your RAM kit at the HWinfo64 memory menu.

The best DRAM kits are made with SK Hynix A-Die, then M-Die.
Then follow a big dip with Samsung B-Die & Micron REV A / REV G.
Another big dip the Samsung D-Die.
The Micron REV B is anti-tuning as far as I know.

If you have A-Die or M-Die, then you can try it.
Foreword: DDR5 RAM settings calculator - make a local copy and you can explore it

Suggestion (and as always: I cannot guarantee anything and can't take any responsibility, just try to help with my personal experience):

-VDD and VDDQ raised to 1.4V
-Timings:
tCL 28
tRCD 36
tRP 36
tRAS 48
tRC 84

The other big thing is the tREFI (Resfresh Rate in ASUS) which can be 49151 or 65535 (the latter is the upper limit az AM5)
The other big thing is the tRFC, this is a hard one, highly depending of the DRAM type:

Hynix A-die DDR5-6000
tRFC: 416

Hynix M-die DDR5-6000
tRFC: 510

Samsung B-Die, Micron REV A, REV G DDR5-6000
tRFC: 832

Samsung D-Die DDR5-6000
tRFC: 864

And if you try anything, first test for a longer period (half a hour minimum) with Aida64 stress test, y-cruncher, TM5 or so.
If you change anything in you UEFI memory settings after the reboot there is a new memory traning phase starting, means longer period of black screen before POST screen.
Be patient and remain calm. :)
If the black screen remain after 4-5 minutes, do a BIOS reset and step back about the changes you made (ie.: if the tRFC 416 wont boot, then try 436 and so on).
Ive been pretty tempted lately to do some tweaking in my ram. I just enabled EXPO and set manually 6000mhz instead of the 6400 of the expo profile (i have 2x32gb and trying to boot with +6000 is probably going to be pretty difficult). My ram is pretty solid, cl32 and SK Hynix A-die, you think i should try these settings?
 
Ive been pretty tempted lately to do some tweaking in my ram. I just enabled EXPO and set manually 6000mhz instead of the 6400 of the expo profile (i have 2x32gb and trying to boot with +6000 is probably going to be pretty difficult). My ram is pretty solid, cl32 and SK Hynix A-die, you think i should try these settings?
From the AGESA 1.0.0.7b version of BIOS (circa 2023 august) I find the AMD covered the memory handling problems of the Zen4 CPU's and mostly can reach the DDR5-6400 without problem.
Means: I bought an Apacer DDR5-6400 kit, put in my system and choose the RAM own XMP (DOCP in AMD) profile and booted without any problem.
So after you have an updated BIOS, I suggest you can try the DDR5-6400 profile. OFC there is a chance it's won't boot, but at least try it once...

Edit: I have a second AM5 computer (HTPC / file server with Ryzen 8500G) that one use the Apacer kit currently while the desktop computer got back the 64GB DDR5-6000 Fury Beast kit.
 

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Ive been pretty tempted lately to do some tweaking in my ram. I just enabled EXPO and set manually 6000mhz instead of the 6400 of the expo profile (i have 2x32gb and trying to boot with +6000 is probably going to be pretty difficult). My ram is pretty solid, cl32 and SK Hynix A-die, you think i should try these settings?

Don't write it off just because it's 2x32GB. As long as your board and memory controller aren't actual garbage, there's a good chance you can. I don't think dual rank is that much of a problem anymore for AMD.

7800x3d 6400cl32 59.6ns.png
 
Don't write it off just because it's 2x32GB. As long as your board and memory controller aren't actual garbage, there's a good chance you can. I don't think dual rank is that much of a problem anymore for AMD.

View attachment 347461
okay then, you both convinced me. Im going to try 6400 today when i get home. I have also set MCLK = UCLK, should i set FLCK manually to 2167 or 2200 or just leave it on auto? ill try first to boot on 6400 and then ill try going from cl32 to 28
 
The FCLK is not attached to the UCLK / MCLK in any way at AM5 / Zen4.
Leave the 2000 Mhz at first, then you can raise that too after the memory run stable.

In my experience the FCLK mostly cause game instability I used the 2200Mhz without problem in everyday work and several stress test (CB23, Aida64).
Yet in gaming I experience constants drops to the Windows desktop. At 2167Mhz I won't experience any such thing...

Silicon lottery at the best...
 
okay then, you both convinced me. Im going to try 6400 today when i get home. I have also set MCLK = UCLK, should i set FLCK manually to 2167 or 2200 or just leave it on auto? ill try first to boot on 6400 and then ill try going from cl32 to 28

You will want to go as much as you can beyond 2000 on FCLK as it will make a difference. How far you get only you can find out for yourself. 2167 is no issue for me at any VSOC but so far struggling a bit with 2200.

FCLK has a tricky relationship with VSOC, higher VSOC helps UCLK but hampers fabric stability. So if you can't boot x FCLK, it may not work at any VSOC you throw at it

Stabilize your 6400 UCLK/FCLK first before you worry about CL28. UCLK stability is distinct from but an important part of ram stability now.
 
OP, enabling MCR has been known for over a year & more now to quicken boot times on Zen 4.
 
I wish AMD would desync MCR from PDM. I can`t see why these 2 features must be linked. PDM introduces extra latency\reduces performance in certain scenarios and is only a sensible feature on notebooks in my opinion.
 
I have it off due to manual timings, voltages and subtimings. No issue with long boot times.

If you don't manually set everything it uses the motherboard algorithm to train every time which is what takes a while. EXPO/XMP only holds basic voltages and main timings.

Simple solution is to set things manually, validate with stability testing, and avoid automatic shenanigans. Fast boot plus no instability.

Better performance too.

MCR breaks some tuning settings as mentioned which leaves performance on the table, often results in eventual instability, and uses mobo auto values for memory, so it's at best stable and slow and at worst unstable and slow.
 
You will want to go as much as you can beyond 2000 on FCLK as it will make a difference. How far you get only you can find out for yourself. 2167 is no issue for me at any VSOC but so far struggling a bit with 2200.

FCLK has a tricky relationship with VSOC, higher VSOC helps UCLK but hampers fabric stability. So if you can't boot x FCLK, it may not work at any VSOC you throw at it

Stabilize your 6400 UCLK/FCLK first before you worry about CL28. UCLK stability is distinct from but an important part of ram stability now.
already did, no issues for the moment, it booted first try. Currently 6400 cl32 2x32gb UCLK=MEMCLK, 2000 FCLK

OP, enabling MCR has been known for over a year & more now to quicken boot times on Zen 4.
Yeah yeah i know, but i also read it wasnt really stable in most cases just some months ago, but it seems is fixed for now. I just wanted to show people how much of a difference it can make
 
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I somehow missed the MCR thing - it might explain random memory BSOD's I have received from time to time (though partially related to BIOS versions).
 
Several firm (like AsRock or MSI) use the MCR enabled by default.
Several other (like ASUS) use the MCR disabled by default.
My MSI board has MCR disabled by default.
 
My boot time from shut down to start is around 9 seconds now.

I have fast boot turned off in BIOS and in power settings of windows 11. it was only slow for me the first boot or two. AsRock must know its stable if they enable it by default... I hope, lmao so far so good so yeah, not had any of the boot time issues others have had and I guess we now know why, in fact I think this board might be the record holder on speed, it is a new re-design mobo so maybe that's why (this mobo just came out in March of this year)

1715814281104.png
 
My boot time from shut down to start is around 9 seconds now.

I have fast boot turned off in BIOS and in power settings of windows 11. it was only slow for me the first boot or two. AsRock must know its stable if they enable it by default... I hope, lmao so far so good so yeah, not had any of the boot time issues others have had and I guess we now know why, in fact I think this board might be the record holder on speed, it is a new re-design mobo so maybe that's why (this mobo just came out in March of this year)

View attachment 347546
Asrock's range of steel legend boards for AM5 are the best for fast boot with MCR enabled. Your boot times to windows match mine. But agesa versions may play into this. I'm still on 2.00 bios.
 
On latest agesa Asus is also very quick currently. MCR and fast startup enabled.
 

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ASrock Steel Legend X670E running 4x16Gb DIMMs with custom timing
 
Asus Prime X670-P WIFI board with UD5-6000 Teamgroup DDR5 Memory 16GBx2.
Missing the last Bios time


Win 11
Task Manager > Startup Apps > Top right hand corner
 
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