Having troubles with high CPU load and really high temperatures

server-linux

#1

I´m running a server on my old gaming PC. On it i have a plex media server installation.
Here comes the trouble. When transcoding movies all my CPU cores gets maxed out (all 8, 4 physical cores with HT).

The setup:
CPU: Intel Core i7 4790K
MB: Asus Maximus Hero VII
Ram: 16GB
Cooling: Corsair Hydro H100i

My server crashes due to the temperatures getting around 100-103 degrees celsius.
Do i have some setting wrong or should i just invest in better cooling.

The server idle temp are around 40-50 deg celsius.
Why are the transcoding taking so much processing power for just one file?


#2

Get a can of compressed air and a vacuum. Time to clean it out!


#3

i built the server a month ago and cleaned everything. Cleaned the CPU and brass plate of the cooler.
Trust me, cleaning is NOT the issue


#4

I've been thinking about this. The Corsair Hydro is no slouch. Whenever I've had problems in the past with heat, if I know the cooling is right, it must be the heat sink compound. What did you use? AS-5 ? If so, did you do the normal curing? While I don't always recommend it, I've had some AMD chips which needed the surface lapped (manufacturing marks)


#5

@ChuckPA said:
I've been thinking about this. The Corsair Hydro is no slouch. Whenever I've had problems in the past with heat, if I know the cooling is right, it must be the heat sink compound. What did you use? AS-5 ?

Yeah I did actually. But i dont know if the Hydro are working as intended in Linux. I cant monitor the performance of the fans and i dont know if they rev up as intended when the CPU gets hot. I´m thinking about chenging the Hyro for a air cooler instead.

The server are standing in a closet but i dont think the ambient temperature are too high.


#6

@ChuckPA said:
I've been thinking about this. The Corsair Hydro is no slouch. Whenever I've had problems in the past with heat, if I know the cooling is right, it must be the heat sink compound. What did you use? AS-5 ? If so, did you do the normal curing? While I don't always recommend it, I've had some AMD chips which needed the surface lapped (manufacturing marks)

What do you mean with the "surface lapped". I cleaned the surfaces with rubbing alcohol. "chemical clean" its called here in sweden ( the name in swedish of course).


#7

Just to ask the dumb questions because I know I've messed it up too.

1. both surfaces cleaned well with alcohol prior to mount?
1. one 1/2 pea worth of AS-5 in the middle of the CPU ?
2. near perfect vertical placement and then twisting as you press down gently for it to spread a bit before you clamp down firmly?
3. 40 hours of continuous on time, cycling from periods of low cpu to higher CPU? (this allows the polymer to melt, spread and then cure)

"lapping" is also known as 'wet sanding" or "polishing"

Some examples of it are: https://www.youtube.com/watch?v=HzPgJjZZLUY and https://www.youtube.com/watch?v=XMFX75oCgto

Regarding the Corsair and the fan control from Linux, if the motherboard can already control air fans it should be controlling it the same way.

I would reach out to Corsair and make sure you're not experiencing a problem. There can be a bad one.
Also, I recommend asking them. You should, worst case, be able to put it in 'maximum cooling' mode. The CPU should stay in the 40C range under full load.


#8

Thank you for the tips. I'm going to check them out more thoroughly when wake up later today.


#9

I still have one question. Why does the transcoder use 600-700% of the CPU? I had an old Core 2 Quad before that never had any overheating problems. It seems strange that my new CPU uses so much processing power


#10

It depends entirely on the codec. HEVC and H264 can go as wide as you have