[SOLVED] Unstable PSU?

Jan 26, 2021
7
1
10
0
Hi guys, I hope someone might be able to help me. I have been having lots of trouble with random restarts, black screens, and now black screens and the GPU fan blasting until the system is reset.
Initially it happened rarely, and only with heavy workloads, since then it's got progressively worse, and can now happen when idle too.

I've been trying to work out what it could be, initially I thought it was the ram, but now I think it might be the PSU. I've been using OCCT to check, and it looks like the 12v rail is unstable? This is the first time for me to investigate something like this, so I'm not 100% sure this is correct. Would someone be able to advise?

Readings in the Bios: View: https://imgur.com/a/n29E3sE


Unstable in OCCT: View: https://imgur.com/a/bqy8BjB


Unstable in OCCT: View: https://imgur.com/a/ea0jEXT


Rare occasion it's stable: View: https://imgur.com/a/6EJBHDK


Any advice greatly appreciated. I've never had issues like this before with the system, it's been solid as a rock.

Thanks.
 

Darkbreeze

Retired Mod
Based on that screenshot, your PSU is on it's way out. I usually recommend discarding any PSU that shows 11.7v or lower when there is no major load applied, as seen in your BIOS screenshot.

Under a load, it's almost a surety that that value is far lower than that, but even at that voltage it's probably enough to cause some problems since it likely is fluctuating intermittently based on your OCCT screenshot.

What is the actual model of your PSU and how long has it been in service?

Try installing HWinfo (NOT HWmonitor or another utility, ONLY HWinfo) and run "Sensors only". Scroll to the system voltages (3v, 5v, 12v) and run something demanding like Furmark or Prime95 and then take a screenshot of what the voltages are, IF it will let you.
 
Reactions: Vic 40 and LV426A

Darkbreeze

Retired Mod
Based on that screenshot, your PSU is on it's way out. I usually recommend discarding any PSU that shows 11.7v or lower when there is no major load applied, as seen in your BIOS screenshot.

Under a load, it's almost a surety that that value is far lower than that, but even at that voltage it's probably enough to cause some problems since it likely is fluctuating intermittently based on your OCCT screenshot.

What is the actual model of your PSU and how long has it been in service?

Try installing HWinfo (NOT HWmonitor or another utility, ONLY HWinfo) and run "Sensors only". Scroll to the system voltages (3v, 5v, 12v) and run something demanding like Furmark or Prime95 and then take a screenshot of what the voltages are, IF it will let you.
 
Reactions: Vic 40 and LV426A
Jan 26, 2021
7
1
10
0
Thanks for the reply and help Darkbreeze.

I tried what you suggested, and it looks like it is almost dropping to 11v, although that was even before I ran the stress test. To be honest it didn't change much during the test, it stayed around 1.7v, but I guess it must be randomly dipping quite hard at times.

View: https://imgur.com/a/bfUR0oR


When it was under load once I saw it dip quite hard shortly before the system black screened, so this must be the cause. This might also be why I can use it sometime and it it works for a while with no problems, and then other times it shuts down almost instantly.

Don't laugh, but the system is about 8 years old lol. Although I replaced the graphics card with an RTX 2080 when they were first released. I have not had any problems with the system pretty much the whole of it's lifetime, including with this new GPU, but it mainly seems to shutdown when the GPU is at 100% and CPU is throttling up and down to 100%.

The PSU is a Corsair TX850M Enthusiast Series TX 850W ATX/EPS Modular 80 PLUS Bronze PSU.

I guess I better get a new PSU at the very least, although I am aware I really need to update the whole system at some point.

Thanks again for your help.
 
Reactions: LV426A
Jan 26, 2021
7
1
10
0
OK great. The rest of the system is.

Asus Sabertooth X79 Motherboard (Socket 2011, Intel X79, DDR3, ATX, PCI Express 3.0, USB 3.0, Thermal Armor, Asus SSD Caching)

Corsair CMZ16GX3M2A1866C9 Vengeance 32GB (4x8GB) DDR3 1866 Mhz CL9 XMP Performance Desktop Memory

Then quite a few SSDs, HDDs and disc drive.

I would like to upgrade the CPU, memory and motherboard in the next year or two, and a RTX 3080 might be on the cards, or the next version after that probably.
 
Then quite a few SSDs, HDDs and disc drive.

I would like to upgrade the CPU, memory and motherboard in the next year or two, and a RTX 3080 might be on the cards, or the next version after that probably.
You should probably get a Seasonic or better 1000 - 1200W PSU then. The "quite a few SSDs, HDDs" could actually be the cause of your voltage fluctuations depending on how many, how old, and what model "quite a few" entails.
 
Jan 26, 2021
7
1
10
0
Is there a Seasonic model you can suggest? My current PSU is 16 x 15 x 8.6 centimetres in size, I don't think I can go much bigger than that, the case just says maximum PSU Length 180mm.

The Corsair CP-9020130-UK TXM seems to be about the right size, but I'd happily go with more watts if I can find something that fits.

The case that I'm using is the Corsair VENGEANCE® C70 Mid-Tower Gaming Case.
https://www.corsair.com/uk/en/Categories/Products/Cases/VENGEANCE®-C70-Mid-Tower-Gaming-Case-—-Gunmetal-Black/p/CC-9011016-WW#tab-tech-specs
 

Darkbreeze

Retired Mod
You don't need more than 750-850w power supply for the RTX 3080 WITH the rest of the system included.

That TX unit would be just fine. If you have a bunch of hard drives and extra fans or other connected accessories, then an 850w unit isn't the worst idea ever.

Please read this:



If your 12v is dropping to 11v, then you clearly need to replace that unit NOW, before it is able to damage anything. Under no circumstances do you need a 1000w or higher capacity unit. That's just nonsense talk.
 
Jan 26, 2021
7
1
10
0
You don't need more than 750-850w power supply for the RTX 3080 WITH the rest of the system included.

That TX unit would be just fine. If you have a bunch of hard drives and extra fans or other connected accessories, then an 850w unit isn't the worst idea ever.

Please read this:



If your 12v is dropping to 11v, then you clearly need to replace that unit NOW, before it is able to damage anything. Under no circumstances do you need a 1000w or higher capacity unit. That's just nonsense talk.
Thank you Darkbreeze and everyone who replied, really appreciate all the help. I ended up going with the 850w unit I posed, and so far, so good. I've been running the main application that was always crashing, and not had any problems. The new PSU seems to be just above 12v, and never seems to dip below that. Still fluctuates a little though, I'm not sure if it should? The 5v seems to fluctuate a little more than the old PSU, but the 3.3v seems to be pretty rock solid. See the screen grab below. I hope this is OK now, but let me know if anything is not as it should be, would appreciate more advise if so. Many thanks.

View: https://imgur.com/a/7QHpe4j
 
Reactions: Vic 40

Darkbreeze

Retired Mod
There will almost always be at least SOME amount of fluctuation in the voltage droop or regulation. Plus, that software probably isn't particularly accurate. Most software isn't, in fact, mostly ALL software isn't really. The only way to get really accurate readings of the voltage regulation and ripple, etc., is using the right test hardware, oscilloscopes, analyzers, etc. With just software, you can get an "idea" of what's going on, but it's probably going to have some margin of error in the accuracy.


I think you are fine if it's working fine now.
 
Reactions: Vic 40 and LV426A
Jan 26, 2021
7
1
10
0
There will almost always be at least SOME amount of fluctuation in the voltage droop or regulation. Plus, that software probably isn't particularly accurate. Most software isn't, in fact, mostly ALL software isn't really. The only way to get really accurate readings of the voltage regulation and ripple, etc., is using the right test hardware, oscilloscopes, analyzers, etc. With just software, you can get an "idea" of what's going on, but it's probably going to have some margin of error in the accuracy.


I think you are fine if it's working fine now.
OK thanks Darkbreeze, that's good to know. And thank you again for all the help.
 
Thread starter Similar threads Forum Replies Date
J Power Supplies 1
Similar threads
Question unstable voltages

ASK THE COMMUNITY

TRENDING THREADS