Zen 4 slow boot: Memory Context Restore, Power Down?

[porina]

 

 

Key components:

7800X3D

Asus B650E-F GAMING WIFI - bios 2613

Corsair Vengeance CMK64GX5M2B6000Z30 6000C30 2x32GB EXPO

 

Ever since I built it, it has been really slow to boot. I never timed it, but the time it takes between hitting power button and reaching POST was very long. Other systems would be at Windows desktop before this even reaches POST. According to task manager the last one was 57 seconds. My Zen 3 laptop next to me was 3 seconds. EXPO on or off didn't seem to make a difference. It even happens on warm restarts.

 

In a bit of searching around, I see suggestion that turning on Memory Context Restore could speed it up significantly. Some reports of instability after doing so, and some interaction with another setting Power Down? My question is, what is the latest understanding on this? I've not been able to find a good write up on this, just endless forum posts that never seem to get anywhere. Might as well start my own and here I am.

 

There is a newer bios since I built the system. The change notes are an unhelpful "improves performance". Might try it later.

 

While I'm here, any other tweaks I could consider? I'm running pretty much stock apart from turning on EXPO.

[PDifolco]

Same here, my 7950x3d takes 1 minute to post at 6000CL30 unless I activate MCR and the related power setting stuff, then it's back to normal 10 seconds 

I think it just stores the previous timings, not sure what else is involved 

[RONOTHAN##]

3 minutes ago, porina said:

Some reports of instability after doing so, and some interaction with another setting Power Down? My question is, what is the latest understanding on this?

Skipping memory training does have the chance at instability, though on the recent BIOS updates the odds of instability is very low. Ever since the 1.0.0.7b AGESA update, MCR has been fairly reliable and I've been running it on every AM5 system I've built. 

 

As for interactions with Power Down, I've never noticed any, so just leave that on auto. 

 

7 minutes ago, porina said:

While I'm here, any other tweaks I could consider?

The Buildzoid subtimings help performance a bit, but if your only goal is to improve boot times, MCR is your best bet. You could also adjust the memory training settings to improve boot times, though that has more of a chance at instability than MCR does. 

[PDifolco]

36 minutes ago, RONOTHAN## said:

Skipping memory training does have the chance at instability, though on the recent BIOS updates the odds of instability is very low. Ever since the 1.0.0.7b AGESA update, MCR has been fairly reliable and I've been running it on every AM5 system I've built. 

 

As for interactions with Power Down, I've never noticed any, so just leave that on auto. 

 

The Buildzoid subtimings help performance a bit, but if your only goal is to improve boot times, MCR is your best bet. You could also adjust the memory training settings to improve boot times, though that has more of a chance at instability than MCR does. 

About subtimings I wasn't able to find them for 2x32GB sticks Hynix M die I got, can I use the Buildzoid ones that are for 16GB sticks?

[RONOTHAN##]

24 minutes ago, PDifolco said:

About subtimings I wasn't able to find them for 2x32GB sticks Hynix M die I got, can I use the Buildzoid ones that are for 16GB sticks?

Yeah, the only difference with dual rank is the SD and DD timings. You can leave them on auto, though IIRC you want to set them to 6/8 for RDRD and WRWR respectively for best performance. 

[porina]

2 hours ago, RONOTHAN## said:

Skipping memory training does have the chance at instability, though on the recent BIOS updates the odds of instability is very low. Ever since the 1.0.0.7b AGESA update, MCR has been fairly reliable and I've been running it on every AM5 system I've built. 

Thanks, I'll give it a try later when I have some time to run stress tests afterwards.

 

2 hours ago, RONOTHAN## said:

As for interactions with Power Down, I've never noticed any, so just leave that on auto. 

I saw many references to it should be on/off depending on setting of MCR. Maybe this was an earlier limitation then? I know I bought Zen 4 relatively late in cycle so what was the case then might not be now.

 

2 hours ago, RONOTHAN## said:

The Buildzoid subtimings help performance a bit, but if your only goal is to improve boot times, MCR is your best bet. You could also adjust the memory training settings to improve boot times, though that has more of a chance at instability than MCR does. 

I found a video, is that it? Not the best format for going over memory settings!

 

I was asking in general if there were any common tweaks. I usually only overclock for fun, as I prefer stability for normal use. Like does undervolting or some curve adjustment do much of anything? I'm really not up to speed on Zen 4.

[RONOTHAN##]

26 minutes ago, porina said:

found a video, is that it? Not the best format for going over memory settings!

Yeah, he did make a patreon post going over them as well, though the video is easy enough to work with. 

 

27 minutes ago, porina said:

Like does undervolting or some curve adjustment do much of anything?

Not a ton, it's worth about 1000 points in R23 by doing a curve optimization. 

 

28 minutes ago, porina said:

I'll give it a try later when I have some time to run stress tests afterwards.

The main issue with MCR is less instability after booting and more the inability to do a reboot. You'll try to turn the system on and it will just be perpetually on the DRAM LED. If you experience that, turn the psu off for a few minutes and hopefully the system will start up again. I wouldn't worry about doing a stress test when enabling MCR, just keep an eye out for this issue.