[SOLVED] High temps and excess CPU usage

WyoPBS · 2013-05-14 15:46:59

I don't know if this is a kernel problem or a hardware problem or what, but it just started yesterday after two things happened -- (1) we went from freezing temperatures to a very hot day and (b) I just did a full upgrade. All of a sudden, CPU usage spiked to the point where my system was almost unusable.

In the past this has been the case with GPU-intensive programs like Second Life, but yesterday even FIrefox would be enough to push CPU over 100% and it would take 5-10 minutes for a page to finish rendering.

The system is a Lenovo H415 with an AMD quad-core and onboard GPU. Right now it's running about 70 degrees F and everything is fine; at the end of a hot day yesterday it was running 100-110 and performance was awful. So I'm 88.472% sure the problem is with the temperature, but I've had this system over two years and last summer only saw performance tank with high GPU usage.

Any suggestions on how I can get this under control? I live in Wyoming where it's not a problem 8 months out of the year... as I said, we had a major snowstorm last week while my friends in Texas and Florida were getting sunburns in their usual 90+ temperatures. And because it's a mostly cold climate, there's no air conditioning... just an evaporative cooler for the few months that it gets hot out. Typically my office, in the direct path of the sun, is 10+ degrees hotter than outside, so if it's 80 outside it's 90 inside.

If this isn't something I can fix with my existing hardware, are there any suggestions for a mobo/CPU/GPU that can keep itself cool when the room is 90 degrees?

Last edited by WyoPBS (2013-05-15 03:37:13)

ewaller · 2013-05-14 16:04:52

Well, your processor should probably not be running at 100% for extended periods; that will drive your power up to the point where the fans will not be able to maintain a reasonable temperature.
On the other hand, a 20 degree C rise in junction temperature over the ambient temperature is not unreasonable.

Now, as I go back and read this, I think there may be a disconnect. You are clearly reporting ambient temperatures in Fahrenheit. I seriously doubt your processor is running at 70F. 100-110F is nothing. Your processor is good to to at least 100C. So, can you clarify your units a bit?

Also, you might consider opening up the box and making sure your heatsinks are not packed with dust.

Last edited by ewaller (2013-05-14 16:06:21)

WyoPBS · 2013-05-14 16:14:38

{shrug} according to gkrellm, it is reporting in F (sorry, I'm born-and-bred American so that's how I configured it!) and it is indeed running 70-80F at the moment. I know different CPUs have different safe operating temps, but I have no idea what is considered safe.
gkrellm output

ewaller · 2013-05-14 16:37:39

Very well, but be aware that your critical temperatures are going to be well over 200F. Closer to 250F.
70F seems a bit low; unless your room temperature is down in the 50's. Any chance that is a heatsink or exhaust air temperature? Your processor junction temperature should be up around 120 to 140F.

WyoPBS · 2013-05-14 17:47:37

ewaller, you might as well be speaking Swahili. I'm an application developer -- ask me about SQL, php, JavaScript, jQuery... even Clipper or Turbo Pascal if you go back that far -- but from hardware I know nothing. I only know what gkrellm is telling me.

My office thermometer is about 4 feet away, on a wall facing the front panel (so, not in the path of any exhaust fans) and at the time I took that screenshot, it was still fairly early in the day and as it happens office temp was about the same, around 70F. I don't know that it makes a difference, but it's a home office in a very small bedroom (maybe 6x10) of a mobile home in a rural area with no protection from sun or wind -- that is, on the open prairie -- and a southern facing window maybe 5 feet away from the computer, with my desk in between.

Today I'm going to set up a large fan in the hallway to help redirect the breeze from the swamp cooler around the corner into my office and out the window.

teckk · 2013-05-14 17:50:28

This machine's CPU temp runs around 90F to 95F when idling - browsing web pages. When encoding with ffmpeg, with all cores running at 100% for an hour, the temp never rises above 145F unless the heat sink and fan are getting dirty. 145F causes no problems.

at the end of a hot day yesterday it was running 100-110 and performance was awful.

That's nothing if you are using the Fahrenheit scale. 110F won't cause any problems. Not unless your heat sink compound is missing or dry.

a mobo/CPU/GPU that can keep itself cool when the room is 90 degrees?

Fans. One on the processor heat sink, one on the power supply, one or more in the case.

but I have no idea what is considered safe.

I've never had any problems with 150F. I've never let one get to 200F

ewaller · 2013-05-14 18:39:36

Okay, a different tack. I do not think it is a problem with your processor overheating. You seem to have plenty of margin between your operating temperature and your critical temperature.

Any chance you have lm_sensors or acpi installed?
Try the commands:
sensors
or
acpi -t
and see what they report.

But, I think your real problem is just a runaway process causing the processors to have little spare bandwidth while consuming a lot of power -- but not enough to cause a critical fault. Maybe a look at what is running using htop will be fruitful.

ewaller · 2013-05-14 19:12:59

WyoPBS wrote:

lm_sensors is a requirement for gkrellm, so I'm pretty sure the latter is just a GUI frontend for the former.
k10temp-pci-00c3
Adapter: PCI adapter
temp1: +24.8°C (high = +70.0°C)
(crit = +70.0°C, hyst = +69.0°C)
radeon-pci-0008
Adapter: PCI adapter
temp1: +24.0°C
But that tells me one thing gkrellm didn't... what the critical temperature is, which is almost three times my current running temperature.
When I first started having problems yesterday, all I had running apart from the baseline kernel and drivers (network, alsa, etc.) was xorg, fluxbox, xterm... and the one process showing in TOP that was out of control was firefox. Chrome (chromium) did the same thing, but gedit did not. brasero ran up a huge spike, too.
One other thing different from operation prior to the upgrade is that now the glx driver is no longer working, so glxinfo/glxgears and Second Life fail to start at all. But that should not affect Firefox etc.
Thanks for helping me understand the hardware issues (or lack thereof). I guess I'll restore back to my pre-upgrade backup Sunday night and see if the problems go away.

No problem, I enjoy it.. (BTW, you hit the 'Report' link instead of the 'Reply' link It happens more than you would imagine)

ewaller · 2013-05-14 19:27:38

But that tells me one thing gkrellm didn't... what the critical temperature is, which is almost three times my current running temperature.

[ewaller drags out his soapbox]
Not really. To express ratios of temperatures, one cannot use C or F. They both have zero at arbitrary points within the scales. One needs to use Kelvin or Rankine. K uses the same units as C, but has its zero at absolute 0 with water freezing at 273K. Rankine uses the same scale as F, but also has its zero at absolute 0 with water freezing at 492R.

So, 24C = 297K. 70C = 343K, so the ratio is really 343/297 or 1.15.

Consider going from a freezing day just south of the Canadian border (32F) going into a 64F degree house. Did the temperature double (no) because,...
going, on the same day North of the border (0C), into a similar house at the same temperature (about)16C house. The ratio cannot be 16/0 .

[ewaller puts his soapbox away]

even Clipper or Turbo Pascal if you go back that far -- but from hardware I know nothing.

UCSD Pascal
Now, you kids get off my lawn !

Last edited by ewaller (2013-05-14 23:23:58)

WyoPBS · 2013-05-15 03:38:16

Marking this solved -- it may or may not continue to behave erratically, but now I know the problem was not due to CPU temperatures as I had feared. Thanks for the quick answers

Arch Linux

#1 2013-05-14 15:46:59

[SOLVED] High temps and excess CPU usage

#2 2013-05-14 16:04:52

Re: [SOLVED] High temps and excess CPU usage

#3 2013-05-14 16:14:38

Re: [SOLVED] High temps and excess CPU usage

#4 2013-05-14 16:37:39

Re: [SOLVED] High temps and excess CPU usage

#5 2013-05-14 17:47:37

Re: [SOLVED] High temps and excess CPU usage

#6 2013-05-14 17:50:28

Re: [SOLVED] High temps and excess CPU usage

#7 2013-05-14 18:39:36

Re: [SOLVED] High temps and excess CPU usage

#8 2013-05-14 19:12:59

Re: [SOLVED] High temps and excess CPU usage

#9 2013-05-14 19:27:38

Re: [SOLVED] High temps and excess CPU usage

#10 2013-05-15 03:38:16

Re: [SOLVED] High temps and excess CPU usage

Board footer