SOLVED CPU gets really hot when converting media...

[zamana]

Hi!

Of course that I try to avoid Plex transcoding at all costs, but sometimes it happens, and every time it happens, my CPU goes high... and get really hot. So hot that the motherboard starts to screaming (and beeps) until I stop the streaming. The temperatures goes to around 100 Celsius/212 Fahrenheit.

By the way, I tried to convert a VIDEO_TS/*.VOB files into an MKV using ffmpeg, but I was forced to stop the process one minute later because of this same behavior.

That's the hardware:
CPU: Intel(R) Xeon(R) CPU E3-1245 v5 @ 3.50GHz (8 cores)
MB: Supermicro X11SSL-CF
RAM: 32GB (DDR4/ECC)

Is there any kind of tuning that can be done to alleviate this load?

Sometimes it seems that this hardware combination wasn't done for this kind of job...

Thanks.
Regards.

 

[colmconn]

Have you got an appropriate cooler on the CPU? Have you checked that the thermal paste is in good condition?

 

[zamana]

Have you got an appropriate cooler on the CPU?

I'm using the original cooler that came with the CPU.

Have you checked that the thermal paste is in good condition?

I'm using the original thermal paste that already came spreaded in the CPU.

Do you think that I could use a different cooler and/or change the thermal paste?

 

[anmnz]

What case? Fans? All working? If you've got adequate airflow through the case the stock cooler should be OK. If not then you are likely cooking your drives too... If airflow seems OK I would definitely start by checking and replacing the thermal paste. A bad connection between CPU and cooler would explain this.

 

[jgreco]

Something's clearly wrong. If there's not airflow, that's the problem. If there is airflow, the thermal system has failed somehow. If it is an active cooler ("has fan") make sure the fan is running. Make sure the cooler is firmly attached (this can be tricky if you aren't particularly experienced with modern CPU's). If it still exhibits, pull the heatsink, clean the crappy stock thermal pad off (use a proper procedure with something like ArctiClean) and then apply something like Arctic Silver 5 being extremely certain to follow manufacturer's recommendations. Using too much thermal paste will make the situation worse.

 

[zamana]

Ok. Sorry for the lack of information.

The case is an NZXT H440. Yes, it's a "game case" but I don't have any "gamer" component. I chose it because it supports 12 HDDs (10 x 3,5'' and 2 x 2,5'').

The case has 7 fans, all working fine: 3 at the front, 3 at the top and one bigger at the back.

My harddrives seems to be fine: the coolest stays around 28C and the warmest around 35C on a typical day (temperatures in São Paulo are around 18 min/27 max right now).

Normal use:

When transcoding:

 

[jgreco]

Graph says it all. Your cooler is failing. This could be a failed fan, a heatsink not sized appropriately, thermal material failure, improper installation, or other issue. A 50'C temp swing is unacceptable.

 

[Jessep]

"Original Cooler" usually means the Intel push pin system that for some reason confuses people. Ensure all four pins are engaged fully, likely best to replace the thermal paste if it has been in use a few years. I would also suggest replacing the HS/F with something more performant.

As jgreco suggested Artic Silver is a good choice for paste (and cleaning tools) I had a Cisco tech come in to replace a failed motherboard in one of our servers and he used an AS cleaning kit (and our AS5 as they forgot to ship the Cisco paste).

I prefer Noctua coolers, a U12S or U14S would last you the life of the CPU and likely at least the next version of your FreeNAS system as Noctua is good about releasing new attachments if Intel changes the sockets. Not cheap though.

 

[jgreco]

Nah, you'd likely be replacing the fan on the Noctua at some point. The thing that works in favor of it is simply the size of the thing.

 

[Jessep]

Experiences vary, in 8 years I've not had a Noctua fan fail or even start making noise.

 

[zamana]

Hi!

I would like to thanks all of you that pointed me towards the right direction.

It turns out that my "cooling system" was completely wrong. There was at least 2 problems:

1) Fan positioning

After search a little bit, I found that I was pushing outside air to inside, from all directions, which is very inefficient. It seems that the correct way is to make the air "flows" from front/bottom to rear/up, like this:

I then switched the side of 4 of my 7 fans and solve this issue.

2) CPU Fan
Shamefully the CPU fan wasn't firmly attached to the motherboard. It was barely touching the CPU. I guess this was the main problem and don't know how the CPU wasn't "fried" during all this time.

3) Result

So, after fixing these issues I was able to sustain an entire midia conversion with no problem. As you can see, the temperature never crossed the 86C degrees during the conversion:

No screams or beeps from the motherboard.

Thanks all of you.

 

[jgreco]

We're always happy to wind up with that pleasant kind of result.

I would note that this still seems to be running quite warm. I suspect that the thermal pad for the heatsink isn't in good condition. Please do consider the whole Arctic Silver cleaning and repasting process.

 

[Jessep]

I would note that this still seems to be running quite warm. I suspect that the thermal pad for the heatsink isn't in good condition. Please do consider the whole Arctic Silver cleaning and repasting process.

Agreed, 80c is too hot for that amount work.

 

[zamana]

Hi!

Ok. So I ended up changing the stock cooler by this Hyper TX3 EVO and the temperatures, when idle, dropped around 10 to 12 degrees (from 34 to 22). And when transcoding, they reach 46/47, but never passing 50 (until now, at least).

It seems a pretty good CPU cooler (and relatively cheap).

Thanks again all of you.