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PC restarts once or twice before POSTing with default RAM speed and fluctuating CPU Clocks & CPU Voltages

Zach_01 said:
Why the heck are you suggesting 1.35V with Core Performance Boost disabled?
If you just disabled that, the CPU will get the appropriate voltage which shouldn't be more than 1.0~1.08V

You only need to disable Core Performance Boost and change nothing else.
Click to expand...
It is also disabled and greyed out in the BIOS due to disabling other OC stuff for the CPU. I have already set it all up manually.
Thanks though.
 
Zach_01 said:
Why the heck are you suggesting 1.35V with Core Performance Boost disabled?
If you just disabled that, the CPU will get the appropriate voltage which shouldn't be more than 1.0~1.08V

You only need to disable Core Performance Boost and change nothing else.
Click to expand...
Well vcore @ 1.35v is plenty for 3.60ghz without stability issue or heat issue as I don't like the idea of the vcore set in auto along with cpu llc. If you let it in auto the temperatures start to get out of control as I seen it with my own eyes. As that why I said it
 
Lundstrm said:
If you read what i have written earlier you would understand that i have disabled this ages ago. It still fluctuated with it disabled by the way.
Click to expand...
Alright then... now remember. Because you cant run DRAM at 3600MHz. And tell me whats the point of running DRAM at 3600MHz if your CPU is not up to the task to use it?
Its better to have the CPU at full boost and DRAM to 3200MHz from what you're doing now.

And you know what else? We might be able to help you to achieve both. CPU at full boost "fluctuation" and DRAM at 3600MHz. But apparently you dont want to listen. Its ok
Today's chips/CPUs got the best performance ever, being dynamic and power efficient all together and we just throw all that down the drain.

Edwired said:
Well vcore @ 1.35v is plenty for 3.60ghz without stability issue or heat issue as I don't like the idea of the vcore set in auto along with cpu llc. If you let it in auto the temperatures start to get out of control as I seen it with my own eyes. As that why I said it
Click to expand...
Do you even own a Ryzen 3000, or are you at least familiar with its stock operating canditions? Because I have one for 19months now and did a lot of testing with it.
1.35V is for 4.0~4.1GHz all core boost (for R5 3600) for a workload similar to Cinebench R20. Not for 3.6Ghz
 
Zach_01 said:
Alright then... now remember. Because you cant run DRAM at 3600MHz. And tell me whats the point of running DRAM at 3600MHz if your CPU is not up to the task to use it?
Its better to have the CPU at full boost and DRAM to 3200MHz from what you're doing now.

And you know what else? We might be able to help you to achieve both. CPU at full boost "fluctuation" and DRAM at 3600MHz. But apparently you dont want to listen. Its ok
Today's chips/CPUs got the best performance ever, being dynamic and power efficient all together and we just throw all that down the drain.


Do you even own a Ryzen 3000, or are you at least familiar with its stock operating canditions? Because I have one for 19months now and did a lot of testing with it.
1.35V is for 4.0~4.1GHz all core boost (for R5 3600) for a workload similar to Cinebench R20. Not for 3.6Ghz
Click to expand...
I don't own a ryzen set up at all as I was helping a friend out by building the system for him as he wanted the max speed from the 3600 without downclocking or power saving features. At the time I benchtested it half a dozen times it get unstable less than the bios was inputting on the vcore. So that why I manually set it up with 1.35v without llc as the vcore would be less according to hwinfo64 and aida64. Temps stayed below 57c on the cpu and cores between 49c to 53c. This what I can recall last time I seen the set up
 
Same issue keeps happening on occasion, i will try an older bios version and see if that works out.
 
Is it rebooting in idle state or during gaming/browsing?
 
Edwired said:
Is it rebooting in idle state or during gaming/browsing?
Click to expand...
it happens when i reboot the pc after gaming or browsing. it restarts once or twice and i think it might even have restarted three times once or twice too
 
It pretty normal for the pc to reboot 2 to 3 times I wouldn't worry about it as mine reboot 2 times before it posts due to the uncore/dram ratio is different. But if it rebooting on it own without warning like during heavy gaming then it might be a problem
 
Edwired said:
It pretty normal for the pc to reboot 2 to 3 times I wouldn't worry about it as mine reboot 2 times before it posts due to the uncore/dram ratio is different. But if it rebooting on it own without warning like during heavy gaming then it might be a problem
Click to expand...
not really normal, especially when the ram speeds resets from 3600 to 2133 after it happens as well...
i don't restart during heavy gaming
 
Well if that the case then I say the reason it goes from 3600 to 2133 generally means the cpu memory controller is unstable or it underpowered due to the restarting it resets the dram speed back to default. I say the best bet is to do abit of research of why it reseting the dram speed
 
Edwired said:
Well if that the case then I say the reason it goes from 3600 to 2133 generally means the cpu memory controller is unstable or it underpowered due to the restarting it resets the dram speed back to default. I say the best bet is to do abit of research of why it reseting the dram speed
Click to expand...
i did, it could be any of these: bad batch of the CPU or my bios version

the CPU should support the speed and the size of the sticks as well
 
Depending on the cpu as it might not be stable at 3600 as the size shouldn't matter. As you might have to do more testing and bumping up the dram/memory controller voltage a small bit
 
Edwired said:
Depending on the cpu as it might not be stable at 3600 as the size shouldn't matter. As you might have to do more testing and bumping up the dram/memory controller voltage a small bit
Click to expand...
As you might have seen i got the Ryzen 5 3600, i use 3600Mhz on the RAM for the 1:1 ratio and yes, the sticks supports 3600Mhz which i've also written before and a voltage increase shouldn't be necessary at all for these sticks to run.

Gonna reflash to an older bios version and see if that makes a difference.
 
Lundstrm said:
As you might have seen i got the Ryzen 5 3600, i use 3600Mhz on the RAM for the 1:1 ratio and yes, the sticks supports 3600Mhz which i've also written before and a voltage increase shouldn't be necessary at all for these sticks to run.
Click to expand...
The sticks are rated for DDR4-3600, but that's based on in-house binning, and doesn't take other variables into account. A CPU with a weaker IMC and/or a motherboard that isn't all that good at memory overclocking (due to low PCB layer count, weak memory topology, etc.) might need a touch more voltage than the 1.35v the sticks are rated for to hit their rated speed.

Have you tried using DRAM Calculator (specifically the Safe profile)? Getting a 4x8 kit stable at 3600 on a lower-end B450 board isn't exactly a walk in the park.
 
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milewski1015 said:
The sticks are rated for DDR4-3600, but that's based on in-house binning, and doesn't take other variables into account. A CPU with a weaker IMC and/or a motherboard that isn't all that good at memory overclocking (due to low PCB layer count, weak memory topology, etc.) might need a touch more voltage than the 1.35v the sticks are rated for to hit their rated speed.

Have you tried using DRAM Calculator (specifically the Safe profile)? Getting a 4x8 kit stable at 3600 on a lower-end B450 board isn't exactly a walk in the park.
Click to expand...
That is true, good point.

Ran into an actual issue now.
I just reflashed the bios to an older version and now I can't get into the bios, it's just a black screen. It boots into windows though.

Lundstrm said:
That is true, good point.

Ran into an actual issue now.
I just reflashed the bios to an older version and now I can't get into the bios, it's just a black screen. It boots into windows though.
Click to expand...
I could get into the bios with F11 but not with "del" as before
 
Funny thing is it usually never the bios that causing the issue in the first place.
 
Edwired said:
Funny thing is it usually never the bios that causing the issue in the first place.
Click to expand...
no, i don't think so either but i just wanted to try it out

milewski1015 said:
The sticks are rated for DDR4-3600, but that's based on in-house binning, and doesn't take other variables into account. A CPU with a weaker IMC and/or a motherboard that isn't all that good at memory overclocking (due to low PCB layer count, weak memory topology, etc.) might need a touch more voltage than the 1.35v the sticks are rated for to hit their rated speed.

Have you tried using DRAM Calculator (specifically the Safe profile)? Getting a 4x8 kit stable at 3600 on a lower-end B450 board isn't exactly a walk in the park.
Click to expand...
DRAM CALC.png


Reflashed to the latest bios again and turned off all of the CPU OC and power saving stuff and i manually set the RAM speed to 3600Mhz this time (instead of XMP) and then 1.37V on the DRAM too, seems stable for now.
 
Last edited:
Cool to hear :)
 
I think the problem is that the motherboard's memory topology can't reliably handle 4 memory modules at this speed. Despite being validated to run at up to 4400MHz with two memory slots populated, the fastest 4-module kit that the B450-A Pro is validated for is 3733MHz which isn't far above 3600, and it's with much looser timings (CL19). The fastest 3600MHz 4x 8GB kit it's validated for is CL17.

As I understand it the motherboard shouldn't significantly affect the stability of different memory timings (which are more dependent on the CPU's memory controller), but it might be enough to push you over the edge into instability in a situation when you're very close to the limit of what the motherboard is capable of. At least in theory, changing the CPU voltage shouldn't have any effect, but based on your description it seems to, which makes me suspect that it could be temperature-related, or possibly some strange cross-CPU electrical effects. It's difficult to say without knowing more about the specifics of what you're running.

Once you've got memory and voltage settings that seem stable, you should try running a memory stability test. A version of hci memtest comes bundled with DRAM calculator for Ryzen, and you can download hci memtest or memtest86 individually. If you run a few instances with around 2000MB each, and wait for their coverage to get up to 100% of your memory (which may take an hour or so) you shouldn't get any error notifications. If it shows any errors, it means that your memory is not stable.

If you need to underclock your memory to get it stable, you could potentially reduce the memory timings to something like 3200MHz CL14-14-14-34 (and tightening some of the minor timings like tRFC can also help a lot). This would give you similar performance to 3600MHz CL16 in most situations.

If you didn't see clock fluctuations with an older Intel CPU it's possible that you had a CPU without turbo boost (e.g. an i3 7100) or that you had disabled turbo boost in BIOS or set a power limit in windows. The clock frequency of most modern CPUs is variable, unless you set a fixed clock multiplier yourself. You will usually get much better performance with a Ryzen 3000-series CPU by allowing it to boost on its own than if you set a fixed clock speed. You can gain performance from a fixed overclock on a Ryzen 5 3600 in some situations if you set the right voltage and LLC, but even if you know what you're doing the improvement is usually very minor.
 
I tried the same voltage (1.37V) with XMP enabled. It seems stable so far and also faster (according to a benchmark) than manually setting them to 3600Mhz.

If it becomes unstable again i'll raise the NB/SoC to 1.1V, like it was when i had them manually set to 3600Mhz on the sticks with XMP off, to ensure stability.

Let's hope that the former remains stable.
I'll be back with another update if it doesn't.

Cheers guys!
 
Lundstrm said:
no, i don't think so either but i just wanted to try it out


View attachment 196712

Reflashed to the latest bios again and turned off all of the CPU OC and power saving stuff and i manually set the RAM speed to 3600Mhz this time (instead of XMP) and then 1.37V on the DRAM too, seems stable for now.
Click to expand...
You need to import DRAM XMP profile for the calculator to suggest the best (in theory) settings.

You can save a report of XMP with Thaiphoon Burner.
Open it and click the "Report" next to "Read". Scroll all way down and click the "Show delays in clock cycles" once to turn into "Show delays in nanoseconds".
Then click "Export" and "Complete HTML Report".
This file you can import in calculator with the "Import XMP" button in main page.
 
I have a 3800X and an ASUS X470 Crosshair VII and I recently bought a 4x8GB RAM kit and I had the double reboot and it would also default back to stock RAM speed. You need to disable XMP and bump the speed a step at a time in the memory speed drop down menu in BIOS (if available in your board BIOS) and ease it up to an OC speed that is stable. I think you are trying to run too much too hot and the CPU doesn't like it. My system didn't like the XMP settings after I switched to default before shutting PC down and switching RAM modules. As soon as I enabled XMP I had issues with the double reboot and system instability even in the BIOS. I currently have them more or less at the rated 3200 speed with more or less XMP timings and they are working fine, but they wouldn't work with XMP settings. My guess is timings were too tight for 4 sticks of RAM to work together.
 
Okay, so like someone wrote earlier it wasn't a walk in the park to get 32GB (4x8) 3600Mhz RAM stable on a low end B450 motherboard like this, but i managed to pull it off.
It started BSODing so i set everything manually instead.
I had to put 1.45V on the RAM (yes, they are passively cooled) and NB/SoC to 1.05V (it was enough) and the rest (CPU ratio and CPU voltage) had to be set manually except the XMP clocks and the timings.

So, in conclusion:
CPU: Ratio at 36.00 @ 1.0V
NB/SoC @ 1.05V
RAM: XMP @ 3600Mhz CL16 (1 CR) @ 1.45V

Gonna consider getting a better motherboard and possibly a better CPU too.
 
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