Strange random freezing/reboots w/ AMD Ryzen 5950X CPU - solved!
Posted by SimplyFreeSpirited@reddit | buildapc | View on Reddit | 46 comments
tldr; - Disable PBO in BIOS, set a fixed CCD0/CCD1 ratio (i.e. 43.00 for 4.3 GHz) (disabling "curve optimization"), and most importantly - set a fixed CPU voltage of 1.25v (a safe voltage for idle/load). Ryzen's dynamic voltage adjustment causes a reboot with older revision 5950X CPUs when the voltage drops too low.
I was having a weird issue where my Ryzen 5950X PC would randomly freeze or reboot in Windows 10. No events logged in Event Viewer either. Windows (or Linux) would freeze during bootup afterwards, before the login screen appeared. This was happening on any storage media I used (nvme SSD, USB stick, etc.). I tested RAM numerous times - no errors. I disabled XMP and ran memory at very conservative settings. I even disabled every performance feature in BIOS - PBO, boosts, etc. - and ran the CPU at base clock speed. The issue persisted. About every week or so, the computer would randomly reboot, regardless of load. This would typically happen in the middle of the night when the system was idle.
I use all high-quality parts and the power supply is no exception. No issues noted with power delivery or other components. Everything is clean and well kept. Drivers and firmware all up to date as well.
The original fix was to load a "watercooled OC" preset in Asus BIOS. That allowed Windows to load without freezing and no more random reboots. However, the processor would easily hit 95 deg. C under load and the system would reboot under thermal constraint. Not good. So I modified the preset's settings to run the processor cooler. Then the issue began again.
After monitoring this issue for over a month, I witnessed what was happening - as the processor's voltage was auto-adjusted continuously, between below 1v and about 1.3v, the reboot or freeze would occur if the voltage went too low. I don't recall the exact threshold but it was about 0.90v. I watched this occur in live time using Ryzen Master.
Somewhere I read that the older Ryzen 5950X CPUs (the revision B0 stepping 0) aren't as stable as newer revisions/steppings. Lo and behold, mine is a revision B0 stepping 0. I have another 5950X system that has a newer stepping (2) that isn't experiencing this issue. Makes sense now.
The proven fix (system running stable 24/7 now for over a month):
- Set CPU core VID (voltage) to a fixed 1.25v, which is safe for 5950X.
- Set CCD CCX0/CCX1 ratios to 43.00, which keeps the CPU at a fixed 4.3 GHz. That may vary for you based on the "silicone lottery"; you may be able to run faster. 4.3 GHz. is the average speed mine operates at and I'm happy with it.
- Set the PPT/TDC/EDC limits manually in BIOS. PPT: 142. TDC: 95. EDC: 140. These are the default standard limits for 5950X. Asus motherboard tends to be aggressive with these so it's good to set them as fixed for stable operation.
- Set PBO "overdrive scalar" to 1X.
- Disable "PBO Fmax Enhancer" or any other proprietary boost algorithms (Asus, etc.).
- Leave "curve optimizer" as "auto". This shouldn't matter as the scalar is 1X and voltage/etc. will now be set to fixed settings.
- "CPU boost clock override" set to "disabled".
- "Global C-state control" set to disabled, to help prevent instability from cores being put to "sleep".
Note that in Asus (and possibly other) BIOS configurations, you may have to enter these settings within multiple screens and sections. The Asus BIOS in particular is a bit of a cluster.
Use Ryzen Master to monitor the temps and such.
Hope this helps anyone having issues with 5950X stability (there's a lot out there from what I see).
SylsOnReddit@reddit
I also have an early Ryzen 5950X that has always been finicky. Last year it started doing random reboots and sometimes they had WHEA codes and it was a couple of the cores crashing - I went as far as to going into overclocking settings and juicing *just those* particular core units to try and stop the crashing, and that worked, for a while.
Then it started again, same crashes as before, but different cores this time. I decided to do what you did and set VID to 1.25v fixed. Turned off my individual core overclocks in the curve optimizer and set that at auto.
I didn't set a fixed ratio as my system usually hovered around 5ghz no problem previously, I left PBO on, but its been stable for a few days now which is a considerably longer period than it had been the past two weeks. If this actually works i'll be very pleased. I've been considering getting an entirely new processor if my 5950X had degraded too much, but if i can avoid that with this fix i'll be very pleased.
treffnix85@reddit
Good evening. I have the same problem with a 5950X CPU on a B550m motherboard.
Disabling Global C-State and setting vCore to 1.25 has helped me for now.
Strong-Pudding-4872@reddit
I never adjusted voltage, but disabling Global C-State ended up doing the trick for me. I've been stable for 48hrs now after turning it off. Prior to that I had already turned PBO and was still getting freezes. I hope other find this and see that disabling Global C-State if your pc freezes while low work load definitely give that shot especially if using a ryzen processor.
Strong-Pudding-4872@reddit
I was experiencing this issue except my freezes were happening any time i was doing light browsing or youtube. When I stressed tested my cpu + memory with OCCT my pc did not freeze once and then once the 1 hour passed of stress testing my pc froze 5 minutes later. I disabled PBO and CBD and neither did anything, only after consulting with chatgpt that recommended I disable global c-state and now for the last 48 hours my pc has been stable no freezes.
brzina13@reddit
After days of random freezes on my Ryzen system, I finally found the root cause and fixed it.
I was dealing with random Windows freezes and WHEA Logger errors (Cache Hierarchy Error). The system would crash even at idle, during browser use, and sometimes under stress tests.
At first I tried the usual stuff:
Nothing fully solved it.
I then checked Windows Event Viewer and noticed WHEA errors pointing to specific APIC IDs (18, 19, 22, 23).
Using CPU-Z, I mapped those APIC IDs to actual cores and found that core 7 and core 9 were the ones consistently triggering the errors.
In BIOS I fixed it by:
After that change, the system became completely stable:
In my case it wasn’t general instability, but a few borderline cores that couldn’t handle default boost/voltage behavior during transitions.
Event Viewer was the key to identifying the problematic cores.
mirkoj@reddit
I had same issue for over a year. finally solved it!
no disabling PBO or anything.
Went to advanced PBO controls and per core control, jsut put 5 positive on 4 best cores.
Best cores identified with amd master that shows first and second best cores.
Since then not a single reboot any more.
thespiderg12@reddit
Can you give me your settings? 🙏🏻
mirkoj@reddit
https://mab.to/t/BJ9pzsbEoMi/eu1 cant upload images here so here is link hope it helps
mirkoj@reddit
Update on my side, no issues at all any more. not a single reboot. All good now!
Puzzleheaded-Body789@reddit
tldr: My CPU is now stable with vcore set to a fixed 1.25V and PBO enabled.
I also have the 5950X rev B0 stepping 0 (asus strix x570-e gaming mobo and 360mm AIO) . When I bought the system, it was completly unstable at the default bios settings! I found that using these settings: PBO enabled and curve optimizer set to negative 6 to all cores the CPU was stable. It was running fine for a few years with these setting but I think my CPU degraded as recently windows 11 wouldn't boot anymore (the loading circle froze and I get a watchdog timeout after some time or something like that). My temporary fix was to use the auto overclocking feature on the asus bios and select gaming/watercooling. But this would set the clocks to a fixed 3.7GHz which kind of sucks for performance. So I asked google what bios settings I should use for my cpu and the most important setting it said was set the vcore to a fixed 1.25V (with a bunch of other tweaks). Well this single setting (1.25V fixed vcore voltage) seems to fix all my stability problems. I even have PBO enabled and it's still stable. No bsod/crash/failed boot for 2 weeks with these two settings so far.
vulcZ@reddit
This is incredibly insane to me. I have had the same CPU and same exact motherboard since 2020, and every once in a while I'd get lockups, at what felt like, the most RANDOM times. They were so infrequent that it was enough for me to ignore them (for the most part). But it was strange because they always happened at times of low CPU load. Anyway, the last month I have wasted so much time trying to solve this issue because it's become so much more frequent. I upgraded my PC but Im giving these old parts to my son, and it got to the point where the system kept freezing during fresh windows installs. I replaced EVERY component, including the CPU with another 5950X I got off Amazon (that now I have to return), and I kept getting crashes. Never in my wildest dreams did I think a CPU, running at completely stock settings, could have stability issues at stock settings. But I think this thread may have saved my sanity. I'm telling you, I have replaced EVERYTHING during this troubleshooting process, and it still freezes. Nothing made sense. But this does.
IWorkForTheEnemyAMA@reddit
Okay so I have the same CPU and found this thread because my computer just started locking up randomly. I have had the CPU for 5 years now, and super stable, then all of the sudden two months ago it would lock up once a week, now I'm lucky to last 10 minutes before it locks. Sometimes it will bluescreen, but that is rare, more often than not it will just freeze completely. I was about to go down the path of rebuilding/replacing and I am glad to read everyone's comments here. I am going to try these settings ASAP.
vulcZ@reddit
In my case, I tried a few different BIOS settings and couldnt get the original 5950X to work properly. However I did get my hands on a much newer B2 stepping 5950X, and surprise surprise, absolutely zero issues. To be completely fair, I didnt invest a ton of time into tweaking the original chip. But I suspect with enough patience and the right settings, you'll find a stable configuration again. I'm still very baffled by all of this.
Shroomdoomed@reddit
I have the same B0 chip and was getting the same idle/sleep reboots. You can actually fix this without locking your CPU to 4.3GHz or a fixed voltage. The goal is to raise the voltage floor while keeping PBO and DOCP active so you still hit 4.9GHz+ on single cores:
After a lot of testing and benchmarking, this seems to have fixed the random reboots for me entirely.
h-ster@reddit
Just to say many thanks! I preferred your solution to pegging the VCORE. When I set the Curve to +5, only lasted an hour so I upped it to +12 and it survived the night. On the other buildapc thread, they mentioned they used +20. The optimum must be based on the silicon lottery and potentially how much the chip had degraded.
Omazing_@reddit
Going to try this for awhile and report back.
I also have the B0 chip and over the past year or two (of course right outside of warranty) I have started having these issues with lockups in lower idle scenarios in both windows and linux. I also don't like the idea of having a fixed voltage for an issue at idle.
I always think I've fixed it after trying something, and then it comes back after a few weeks/months.
I feel like this issue is under reported on, I have read dozens and dozens of threads trying to fix this issue and others like it and it seems like ryzen 3 and 5 series chips are all having major silicon degradation issues.
I guess that's just the problem with modern boosting technology pushing the envelope too hard.
My i7 4790k still happily chugs along as a server box with probably a few drips of liquid coolant left in the ancient h100i I bought used even then. I'm starting to worry this 5950x won't ever get to become the server computer I hoped it would be in a few years when I upgrade my main rig.
Omazing_@reddit
Update: Been 12 days haven't had a lock up or freeze in either operating system.
Unlikely_Capybara@reddit
thank you mate, I will try this too. I didn't play with PBO mode/limits before.
smashT@reddit
Thanks, this appears to have fixed my issue, was pulling my hair out
dsngiem@reddit
I was able to stabilize my MPG B550 GAMING CARBON WIFI with Ryzen 5950X and Windows 11 by disabling Global C-state Control (all my other settings are the BIOS defaults). I did not have to touch the other settings in my case. Should it become unstable, thanks for writing down the other configuration options to consider.
Are there settings that you would prioritize testing before others?
Unlikely_Capybara@reddit
This did help me too but not any more.
- first 2 years - had zero stability issues [Asus X570 + ryzen 5950]
- after that, for about 2 more years "Global C-State = Disable" was working fine
- in the last \~1 year the problems returned, even global C-State does not work any more. I am trying to increase the CPU voltage using Offset mode, but I'm not sure what I'm really doing. Asus BIOS layout is a mess.
testaccount123x@reddit
this fixed it for me on my old motherboard (some rog strix thing, forgot which one) I think i disabled c state control and something to do with power supply idle control I think it was called, if anyone else sees this, try those 2 things first. that was the key on that mobo, but on my new one (asus tuf a520m) it didn't do the trick, so I'm gonna try all these settings from this post once I get another freeze/restart.
testaccount123x@reddit
This thread saved me. On my old motherboard, the global c state thing fixed this issue for me, but on this new mobo with the same processor, that setting wasn't enough for me.
I have the
ASUS TUF Gaming A520M-PLUS (WiFi)and this didn't have any of the overclocking settings that you mentioned. It literally only had the global c state, which was already disabled but hadn't fixed it, and then because of this thread I manually set the voltage to 1.25v and It's been about a day and I haven't frozen/crashed yet, which has never happened before. So I think it's good.thanks again for this post
AbzRaider@reddit
a A520M board may have weak vrms shld get a better board
Phalanks@reddit
I'm going to kiss you on the mouth.
Something like a year ago my PC stopped booting into any os. Windows hung at the spinning circle like someone else mentioned. Linux boot drives would just randomly freeze while booting. I couldn't find ANYTHING, so I ended up building a new PC, but now I want to use my old one for VMs.
Just changing the voltage to 1.25 let me boot into the OS and setting it to a +0.05 offset is doing the same. I literally just did it, so we'll see if it's stable long term.
Ok-Comfortable-9258@reddit
Setting LLC to level 3 also fixed my issue.
I was having the same issue and I tried the locking voltage fix first. It worked, but I didn't like the idea of having a fixed voltage, so I tried some other options. The LLC setting is the only one that seemed to prevent the issue, although I also have my idle power set to standard instead of low right now too. I plan to try lowering LLC and setting the idle power back to low also, but wanted to share that the LLC fix might also work for folks.
TorazChryx@reddit
Rake (2010) - The Australian version, there's a US remake which I haven't seen so I can't vouch for it either way. but the Aussie version is fantastic.
TL;DR - Show about a scumball lawyer, it's pretty great honestly.
SimplyFreeSpirited@reddit (OP)
Update: Over 2 months later, no further issues.
admalledd@reddit
If this fixes it for me, I'll owe ya one. I knew it was cstate related, I'm on Linux and been using the Zen power module to disable c6 for over a year now. That helped for a while, but it's started coming back and randomly decided to Google to see if anyone else has the problem. Previously that only led me to software disabling of c6, which only helped for a while
LocutusvonBorg@reddit
i have a 5950X revision "VMR-B2", Stepping "2" and it happened to me as well, after roughly 4 years
SimplyFreeSpirited@reddit (OP)
That's about the time mine began having the issue. No changes to BIOS firmware/etc. beforehand either.
chum_is-fum@reddit
Quick question. How long did it take you to find a solution to this? I have been having this problem for a few gears and lost count of how many hours i spent trying to fix it. This has been a huge help.
SimplyFreeSpirited@reddit (OP)
It took me a few months. The system would randomly reboot every few days, last about a week on occasion. It has been running 24/7 for over 2 months straight now.
chespin731@reddit
Ich hab schon alles versucht. Bekomme die CPU einfach nicht STabil, selbst mit allen Settings und auch unterschidliche kombinationen.
Der PC Friert of im leerlauf ein. Aber immer friert erein NACH einem CPU Stresstest.. Wenn ich eine Endlosschleife mache friert er nie ein, erst wenn die CPU last wieder droppt. Selbes beim Rendern in Fusion 360.
-Temperaturen sind alle im Grünen Bereich. VCORE Spannung immer über 1.100V.
-Das ganze unabhängig von der LLC Einstellung
-Anderen RAM auch schon getestet & nur mal einen Riegel.
-Bios, Chipset Treiber etc alles aktuell
Vielleicht hat noch jeman einen Plan?
Verwenden ein Aorus X570 I Pro WIFI + RX570 8G + Corsair RM850 PSU + 5950X
LocutusvonBorg@reddit
hast du denn genau die sachen alle gemacht, die er oben beschrieben hat? bei mir hat es vermeindlich geholfen, kann ich erst später sagen. immerhin freezed er jetzt nicht mehr und das schon seit über 30 minuten. vorher wäre da 30 freezes gewesen...
mixxen@reddit
Thanks! My system began crashing randomly at idle just a few days ago. I have a 5950x on a x570 AORUS. Turned off global c-state, and the system has not crashed yet. Previously, I had set the minimum CPU load to 10%, but that no longer provided stability. I suspect the CPU is degrading and will eventually die...maybe I can get a couple more years out of it with this workaround.
286893@reddit
You're the goat, it's been months of troubleshooting for me on my 5950x
testaccount123x@reddit
same, lmao. crazy how many of us are dealing with this same thing. just months of freezes and restarts daily.
sketchiegamer@reddit
This issue just started with my system just this week. something is up. its been stable for years and all of a sudden this. I can usually leave my computer running for days any come back to it and its fine but something recently has caused this.
ljw88@reddit
Recently upgraded to a 5950x and having random CPU crashes overnight when idling or when screen has been off... if I don't turn the screen off it seems to sit there just fine. There was a low load current setting in bios I just changed but will likely have to do some more diving.
Ok-Zucchini133@reddit
Same problem here on windows 11 with the same cpu with asus x570 e gaming and msi 4090 suprim
tested my drives and rams everything is ok
My pc just reboot on idle and freez on asus logo on startup, turn off pc with power button and run it again same issue until I turn off psu off/on then automatic repair shows then the pc works
Is your fix all on bios? I will try to do what you did hope that will fix mine also
sandspike@reddit
Your information and ChatGPT helped me solve this issue on my son's 5900x rig that I built. It has run fine for years.....then crashes on boot and low load....it you run a disk scan, no crashes. So it appeared to be a voltage droop that caused a hard lock (frozen screen), not blue screens. I think the silicon has degraded over time or something else changed.....not sure what.
This was my solution.
Stable BIOS Configuration — Ryzen 5900X + MSI MPG B550 Carbon Gaming WiFi
✔ CPU Settings
* CPU Core Voltage: Manual – 1.25V
* Precision Boost Overdrive (PBO): Auto
* CPU C-States: Disabled
✔ Memory Settings
* DRAM Voltage: 1.35V
* (Typical and correct for DDR4 XMP profiles)
✔ PCIe / Chipset Settings
* ASPM (Active State Power Management): Disabled
Why This Configuration Works
* Manual 1.25V Vcore:Prevents low-load voltage dips that were causing random freezes.
* C-States Disabled:Stops the CPU from entering low-power states that can be unstable on some Zen 3 + B550 combinations.
* ASPM Disabled:Prevents PCIe link power management issues at idle/light loads.
* DRAM at 1.35V:Ensures memory runs at proper XMP voltage for stability.
scorsy63@reddit
I've been having the same issue, random restarts when idle/light load but never during heavy load like gaming etc.
I'm also on Win 10 and I OC'd my 5950x with Ryzen Master using PBO.
I tried 2 things and I think it fixed my issue.
- Set LLC(Load Line Calibration) to level 3 (default auto)
- Set Global C-State Control to on (default auto). Setting this to disabled made my system even more unstable. I had some BSOD while gaming.
It might be too early to tell because I just made these changes a few days ago, but so far I have not had one random restart. Also my cpu is still hitting 4.8/4.9 GHz peak speed.
WhySuchALongName@reddit
You are a lifesaver. I've been having issues for 2 months, where my PC just randomly freezes at least once a day, requiring a restart. I tested every piece of hardware, updated all my drivers, updated the BIOS. Nothing helped.
Yesterday, it got to a point where within 1 minute of booting, my PC always froze, making it completely unusable. I booted into safe mode and tried turning drivers off but nothing helped.
I even reinstalled Windows 11 this morning and it was freezing during the install process.
Then, after about 20 other useless reddit threads, I found this one. I made a few of the changes in the BIOS that you mentioned (not all of them because I couldn't find some), and it fixed it.
I wish I had found it before I reinstalled Windows, but I'm just so happy that I finally found useful advice. Thanks!
BartonChrist@reddit
Interesting! Thanks for sharing the solution you found. Is there a way to find if a 5950X is one of these older revisions?
SimplyFreeSpirited@reddit (OP)
I use CPU-Z (freeware) to show the CPU technical details