PC Resets, only when I’m not using it!

Ghuraba

Ghuraba

Ghuraba

Associate
Joined
17 Oct 2002
Posts
1,374
Location
Leeds
Hi there.

I have a very strange problem. My PC is fine when I’m using it, gaming, stress testing you name it. No problems, no crashes and no reboots as long as I leave it on the PC HDMI input on screen. But if I leave it running and switch inputs to say watch TV, I use my LG C9 as my input, then sooner or later it reboots. I did a full reinstall today of Win 11 as my PC is 6 years old and I haven’t used it in 18 months. But it just rebooted. I have put a new battery in the MB incase it was this etc.

Any thoughts? Can a loss of signal from the TV to the GPU cause a system reboot? LG TV well known for handshake issues.

Temps are fine, all software up to date, bios and drivers etc. stress testing OCCT, Prime95, 3Dmark, gaming, Aida64 perfectly fine no crashes.

5800x3d
5070ti
Corsair 850w
32GB RAM
 
Last edited:
Anything in the event viewer before the reboots?

You could try disabling C-States to see if there's a low idle issue, low undervolts can also do that (curve optimiser). Not sure what you could do about the graphics.

Is the PSU a modern variety? Some very old PSUs have problems with very low power draw.

It could be completely unrelated to the above, I'm just speculating because having no screen might be pushing it into a low idle state.

How is the LG C9 grounded? Does it have a euro plug?
 
PSU is quite new Corsair 850x. UK plug for the TV. I do have a curve optimiser .985v with Asus Tuf 5070ti OC. Boost to about 3GHZ. C- State will try. Process of elimination action. Maybe reset the GPU O/C see what happens first.

Event viewer just has kernel 41 msg that PC didn’t shut down properly.
 
Yeah. -25 offset. Thing is I haven’t used my PC in over 18 months. Decided to get it going again. But back then I was using an app to set the under volt in windows each boot -30. But I updated my bios and now they added a feature in the bios to do it. Plus I had a 4090 then which I sold and now have a poultry 5070ti. Everything else is as it was back then with no issues before.

Maybe the bios curve is more accurate or aggressive than the app I used to set the curve each boot.

Anyway a few options. Set clocks to default see how it goes, turn of C State or don’t be much bothered as I don’t normally leave my PC on while afk and while actually using it it’s perfect.
 
Yeah. When I ran OCCT core 4 had thousands of errors at -30 lol. So I turned all down to -25 offset. Everything after this test wise was a pass.
 
idle is very hard to test for, you just have to leave it idling and see what happens

I'd say you need to back off more. Ideally you'd want to dial in the offset for each of your cores rather than 1 setting for all cores. However, I did that during covid with my 5950X and know that can take a lot of time to do properly
 
So I did a fresh windows install, reset the bios and loaded defaults, no overclocks and just drivers updated. I’m still get random shutdowns at idle, meaning PC is on but I’m not using it. I’m wondering if now it’s hardware that’s faulty. The GPU 5070ti is the only new component and it’s been happening since this was installed. I have a spare PSU too I might switch.

Works perfect while using and not a single crash etc.
 
Last edited:
Have you checked Windows Event log at all? I think should be looking for ID 6008, with a message like "The previous system shutdown at 18:28:34 on ‎24/‎03/‎2026 was unexpected." That will give the exact time of the last shutdown, so with that exact time you can then look closer at other events just before it.
 
Yeah. Background intelligence transfer last log before restart this time. I’ve flashed back to an older bios as when I brought my PC out front the dust I’ve updated to the latest bios and got a new GPU. Updated to WIN 11 from 10

Gonna try my old PSU too. Seems power related. Hard to know.
 
Ghuraba said:
Hi there.

I have a very strange problem. My PC is fine when I’m using it, gaming, stress testing you name it. No problems, no crashes and no reboots as long as I leave it on the PC HDMI input on screen. But if I leave it running and switch inputs to say watch TV, I use my LG C9 as my input, then sooner or later it reboots. I did a full reinstall today of Win 11 as my PC is 6 years old and I haven’t used it in 18 months. But it just rebooted. I have put a new battery in the MB incase it was this etc.

Any thoughts? Can a loss of signal from the TV to the GPU cause a system reboot? LG TV well known for handshake issues.

Temps are fine, all software up to date, bios and drivers etc. stress testing OCCT, Prime95, 3Dmark, gaming, Aida64 perfectly fine no crashes.

5800x3d
5070ti
Corsair 850w
32GB RAM
Click to expand...


Let me guess you have a Ryzen cpu

Common issue

Reset bios is to default settings and see if it fixes it
 
Last edited:
Yeah. But I’ve had this cpu years and it never happened. Done all resets. Gone to an older bois right now.
 
Last edited:
I’ve left my PC in the bios and it has not restarted once. Not sure what that tells me. If it is hardware would you expect to repeat the fault. Bearing in mind I’m having no issues while using the machine or stressing all parts, not a single crash or reboot. Just idle issues resulting in a reboot. I suppose the idling in the bios is as stress less as you can get.
 
Last edited:
Hmmm. So if it’s fine in the bios but reboots at idle in windows it suggests software you think? Bear in mind I’ve turned all power saving settings off in the bios previously like C State, PSU idle, bios at defaults with no overclocks on cpu, ram or GPU with a clean windows etc. Not changed Windows Balanced power saving plan though.
 
Ghuraba said:
Hmmm. So if it’s fine in the bios but reboots at idle in windows it suggests software you think?
Click to expand...
Not necessarily, but if C-State is off and no curve optimiser then it is unlikely the CPU idle states.

Ghuraba said:
I have a very strange problem. My PC is fine when I’m using it, gaming, stress testing you name it. No problems, no crashes and no reboots as long as I leave it on the PC HDMI input on screen. But if I leave it running and switch inputs to say watch TV, I use my LG C9 as my input, then sooner or later it reboots. I did a full reinstall today of Win 11 as my PC is 6 years old and I haven’t used it in 18 months. But it just rebooted. I have put a new battery in the MB incase it was this etc.

Any thoughts? Can a loss of signal from the TV to the GPU cause a system reboot? LG TV well known for handshake issues.
Click to expand...
Personally, if this remains true, that it only reboots with the LG C9, then I'd suspect either: the card's handling of power states. An issue with the grounding of the monitor, like the cable, or a surge protector.

The former can be tested by running something else (3D) in the background to hold the power state, like a low-demand game, the latter can sometimes be mitigated by using an adapter e.g. HDMI to DP.
 
Last edited:
I've a C9 as my TV and sometimes the HDMI just doesn't like switching. for example If i'm watching sky and switch over to to the PS5 It'll give the blank screen thingy even I often have to switch inputs a few times for it to "latch" on.

Which has got me thinking about your issue. This isn't a control by HDMI issue by any chance. Is the PC thinking theres nothing connected so powers down after a while.
 
mattyg said:
I've a C9 as my TV and sometimes the HDMI just doesn't like switching. for example If i'm watching sky and switch over to to the PS5 It'll give the blank screen thingy even I often have to switch inputs a few times for it to "latch" on.

Which has got me thinking about your issue. This isn't a control by HDMI issue by any chance. Is the PC thinking theres nothing connected so powers down after a while.
Click to expand...

I was under the impression that even if my PC was not connected to a display that if it’s on it will keep running unless it’s set to turn off to save power in windows etc. I can test it by removing the HDMI cable.

The handshake issues you mention I’m familiar with. Turn the TV on/off, instant gaming response on/off and change inputs most of the time picks it up again. On a rare occasion a PC reboot is needed.
 
You must log in or register to reply here.
Back
Top Bottom