Question 5900x insane idle temps, no idea what to do, please help

Nov 27, 2020
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My 5900x is constantly running at 90-95 °C, even when idle and when the actual cpu usage is just 5%.
All fans are on max speed and liquid cooler is also on max according to bios.

I have no idea at all what could be causing this or how to fix it, please please help.
If you need any extra information, let me know and I'll answer as fast as I can.
 

DSzymborski

Titan
Moderator
Not sure, but according to the bios it's running at around 3500 RPM, and the RGB lights are also still on.

Can you feel the pump while it's on? How do the tubes feel?

Basically, it's a basic exercise in thermal dynamics, so only a few things can practically be wrong. Outside of a rogue crazy overclock (which you could check for easily), it's either failure of a cooling device or failure of the mount or some other aspect of the install.
 
Nov 27, 2020
39
1
535
Can you feel the pump while it's on? How do the tubes feel?

Basically, it's a basic exercise in thermal dynamics, so only a few things can practically be wrong. Outside of a rogue crazy overclock (which you could check for easily), it's either failure of a cooling device or failure of the mount or some other aspect of the install.
One of the tubes feels warm while the other feels normal. I haven't overclocked anything yet and I also double checked the mounting.
 
I just opened my case to check and yes, one pipe is warmer than the other. Is the cooler broken?
Actually that is a good thing. One pipe is cold/cool water in and the other is warm/hot water out back to the radiator. This indicates there is water flow in the AIO which would not be the case if there was an airlock or pump problem.

At this point I would consider remounting the pump with fresh thermal paste.
 
Actually that is a good thing. One pipe is cold/cool water in and the other is warm/hot water out back to the radiator. This indicates there is water flow in the AIO which would not be the case if there was an airlock or pump problem.

At this point I would consider remounting the pump with fresh thermal paste.
Technically that means little coolant flow. The water temp rises as a whole. Both tube temps should be almost indistinguishable by touch after prolonged load.

One of the tubes feels warm while the other feels normal. I haven't overclocked anything yet and I also double checked the mounting.

I'm thinking the impeller is airlocked and not actually moving fluid. Or the impeller broke off pump shaft and not spinning at all. Try tapping on the pump with the handle of a screwdriver. Or even better, when it's removed for repasting, give it a couple taps and shake it around.
 
Nov 27, 2020
39
1
535
Actually that is a good thing. One pipe is cold/cool water in and the other is warm/hot water out back to the radiator. This indicates there is water flow in the AIO which would not be the case if there was an airlock or pump problem.

At this point I would consider remounting the pump with fresh thermal paste.
Tried already :/ but thanks for the suggestion!
 
Nov 27, 2020
39
1
535
Technically that means little coolant flow. The water temp rises as a whole. Both tube temps should be almost indistinguishable by touch after prolonged load.



I'm thinking the impeller is airlocked and not actually moving fluid. Or the impeller broke off pump shaft and not spinning at all. Try tapping on the pump with the handle of a screwdriver. Or even better, when it's removed for repasting, give it a couple taps and shake it around.
I think so too, nothing else points at any issues except something with the pump. I'm gonna try and will update here asap.
 
Nov 27, 2020
39
1
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Yeah, coolers can cool because of speed of the flow - a delta of about a degree C from inlet to outlet temperature is common. Given the materials that you're feeling, I'd be surprised if you could noticeably feel the difference, especially with your eyes closed and someone else randomly orienting it for your hands.
Yes the difference is very noticeable, something must be wrong with the pump. I'm about to try drivinfast247's suggestion and I hope it works.
 
Technically that means little coolant flow. The water temp rises as a whole. Both tube temps should be almost indistinguishable by touch after prolonged load.
I’ve been able to feel the difference on the few AIO’s I’ve used. However, that could easily have been without the system running for prolonged time as it’s been a quick test when it’s on the bench. Might give it a go later after it’s been on for an hour or so.
 
Nov 27, 2020
39
1
535
Technically that means little coolant flow. The water temp rises as a whole. Both tube temps should be almost indistinguishable by touch after prolonged load.



I'm thinking the impeller is airlocked and not actually moving fluid. Or the impeller broke off pump shaft and not spinning at all. Try tapping on the pump with the handle of a screwdriver. Or even better, when it's removed for repasting, give it a couple taps and shake it around.
I tried it and also reset my bios to default, then did a test, now it's on 50-64 °C when idle, around 75 °C when browsing chrome (10 tabs open) and around 90 °C when chrome (10 tabs) + playing any game or when browsing chrome + updating a game. Already much better! But I'm not sure, are these normal temps now?
 
Nov 27, 2020
39
1
535
I tried it and also reset my bios to default, then did a test, now it's on 50-64 °C when idle, around 75 °C when browsing chrome (10 tabs open) and around 90 °C when chrome (10 tabs) + playing any game or when browsing chrome + updating a game. Already much better! But I'm not sure, are these normal temps now?
Just as additional information, my idle temps used to be around 30 when I had first built the system, and 25 was the lowest I ever got it.
 
the whole 'one tube warm, the other at room temp' more than likely means it is not pumping at all....; where the tube is warm is likely just stagnant/non-moving water relatively close to the underside of the pump where it contacts the heat-shield surfaces.

(not sure why folks think warm water can be brought back down to 22C temps in one quick pass thru a radiator, but, it does not happen quite that efficiently or quickly or thoroughly)
 

KyaraM

Admirable
I tried it and also reset my bios to default, then did a test, now it's on 50-64 °C when idle, around 75 °C when browsing chrome (10 tabs open) and around 90 °C when chrome (10 tabs) + playing any game or when browsing chrome + updating a game. Already much better! But I'm not sure, are these normal temps now?
90°C shouldn't happen from just a couple Chrome tabs while gaming, so no. My 12700K is a pretty hot-headed CPU, and doesn't spike that high even having a game and 10+ browser tabs running, in one of which plays a YouTube video. Gets to maybe 70 tops in that situation, and that's quite a bit more load. And I use air cooling. So even if Intel and AMD aren't 100% comparable in this regard, your CPU should never run that hot in such situations.

Also, the fact that your system initially ran at 30 idle but doesn't anymore should already tell you that there is something amiss now. 25-30°C is where my system is sitting idle, 30-40°C with light load. Gaming starts at around 48-53°C average temps. I think your AIO gave out on you, or nearly.
 
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Nov 27, 2020
39
1
535
90°C shouldn't happen from just a couple Chrome tabs while gaming, so no. My 12700K is a pretty hot-headed CPU, and doesn't spike that high even having a game and 10+ browser tabs running, in one of which plays a YouTube video. Gets to maybe 70 tops in that situation, and that's quite a bit more load. And I use air cooling. So even if Intel and AMD aren't 100% comparable in this regard, your CPU should never run that hot in such situations.

Also, the fact that your system initially ran at 30 idle but doesn't anymore should already tell you that there is something amiss now. 25-30°C is where my system is sitting idle, 30-40°C with light load. Gaming starts at around 48-53°C average temps. I think your AIO gave out on you, or nearly.
Yeah I was thinking the same thing. Ordered a new AIO, if the new one brings it back to normal temps, perfect, if not I can just return it but then I have to find out what the actual issue is. Pretty sure it's the AIO though, everything else is working completely fine.