CPU stands for Central Processing Unit, and is the main processing chip used in every computer. Brands include Intel, AMD and ARM. CPUs are commonly available in 32- and 64-bit, and come in a variety of frequencies or with multiple cores.

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177
votes
10answers
320k views

How do I get the CPU temperature?

How do I get the CPU temperature?
68
votes
6answers
177k views

Kworker, what is it and why is it hogging so much CPU?

I recently upgraded to the Kubuntu Natty Beta 1 and I've been having a lot of issues with the process kworker. At moments it uses almost half my CPU. Also, strangely enough it seems to affect my USB ...
22
votes
3answers
43k views

Why does kworker cpu usage get so high? [duplicate]

I recently installed Ubuntu 12.04 on my Samsung laptop alongside Windows 7. Whenever I use Ubuntu (even when its idle) kworker uses almost 90% of one of 8-cores. Even though it doesn't really affect ...
26
votes
5answers
198k views

Kernel requires an x86-64 CPU, but only detected an i686 CPU. How can I install Lubuntu/Ubuntu?

I'm trying to install Lubuntu on my laptop (sorta old 2005). [Laptop stats: Intel® Celeron® CPU 410 @ 1.46 GHz 1.47GHz, 448 MB of RAM] I press Install and this message appears: This kernel requires ...
77
votes
6answers
144k views

Any way to check the clock speed of my processor?

Is there any way to check at which clock speed my processor is running? I have already tried cat /proc/cpuinfo but the clock speed I'm running isn't showing. I know Ubuntu 12.04 (Precise Pangolin) ...
0
votes
1answer
290 views

My cpu slows down after a while and does not recover

Sometimes, and I can't reproduce it (but it happens often enough - a few times a week at least) my cpu slows down below its prescribed minimum. This is an example cpufreq-info output from a minute ...
30
votes
4answers
23k views

Is Ubuntu optimized for multicore CPUs?

Does Ubuntu make use of multicore CPUs (as Windows 7 is said to do)? In other words, is it multitasking optimized so that users will take benefit of 4+ core processors?
5
votes
2answers
3k views

14.04, I have Disabled CPU throttling, but installing Atlas says: “CPU Throttling apparently enabled”

My PC is using ubuntu 14.04, and I need install Atlas. Atlas says: it need to disable CPU throttling, I have done the job to disable it. cat ...
22
votes
3answers
50k views

How to determine if CPU VT extensions enabled in bios?

I know the command to figure out if a CPU can support VMware Workstation 8 or VMware Player 4: $ grep flags /proc/cpuinfo flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov ...
0
votes
2answers
6k views

HP Pavilion G6 1209 temperature higher than usual and fan working in 11.10

Installing Ubuntu on this new machine i had various problems, so I asked around ask ubuntu for a solution. This is the latest one! :D When I start the pc it shows the temperature around 50-55. When I ...
33
votes
2answers
117k views

CPU temperature monitor for 14.04LTS?

Is there a way to configure psensor so the temperatures read out in real time in the panel so it could be read at a glance? So far, in order to read the temperature I have to click on the applet ...
14
votes
4answers
19k views

When will we get Sandy Bridge support?

I'd like to build a machine running Ubuntu and using the new Sandy bridge (i5 2500 specifically) intel cpu's. I heard that 10.10 doesn't have the best support (or simply won't work) with the new cpus ...
8
votes
3answers
44k views

How I can disable CPU frequency scaling and set the system to performance?

My processor is running at 40% of its maximum speed, I want it to use 100% of the speed, all the time. I searched on Google but the tutorials are very old and they all differ. So, how can I ...
13
votes
2answers
7k views

Maximum CPU frequency stuck at low value

I have observed a problem with Ubuntu 13.04. The problem was not there on 11.10 I used earlier. The maximum CPU frequency is stuck at 2GHzon my Intel(R) Core(TM) i7-2620M CPU @ 2.70GHz (Dell Lattitude ...
11
votes
4answers
18k views

Getting Processor Information

I have just ran lshw to get some information about a machine I know nothing about, and I just wanted to confirm something. Does this basically mean it is a dual core 64 bit processor that is ...
18
votes
2answers
37k views

High CPU usage without a process to blame. What is [migration/x]?

For the past few days my computer has been revving its fans while not doing very much. I'm talking an instance of Firefox, gedit, few terminator windows and that's about it. I have conky running on my ...
5
votes
1answer
9k views

Should I activate the additional driver: Processor microcode firmware for Intel CPUs for intel-microcode

I have recently noticed that there is an additional driver called Unknown: Unknown here which was not there before: I have already read this, and understand why it is there, but my question is, ...
3
votes
3answers
2k views

Hyperthreading on 32-bit but not on 64-bit?

I have a strange situation. I have two computers with identical hardware, both Core i5, exactly the same model. The only difference is the OS, one has 12.04 32-bit and the other one has 12.04 64-bit. ...
11
votes
4answers
10k views

100.0% usage by Audio codec hwC0D0: Realtek

I ran powertop, and it says that the Realtek audio codec is using 100.0% of the cpu. Is this a problem? I'm running Ubuntu 11.10 32-bit on Intel® Core™ i7 CPU M 640 @ 2.80GHz × 4 Sony VAIO laptop.
7
votes
4answers
19k views

What is the current frequency of my processor (CPU-Z equivalent)?

Is there a ubuntu program like CPU-Z which will show me the actual frequency of my processor? I do a fair amount of scientific computing which leads to me running my programs for up to 10 hrs. To ...
5
votes
4answers
13k views

Is there any version of Ubuntu that does not require PAE?

For the first time I tried to install Xubuntu 12.04 on my computer using the Grub4dos way. However, it stuck and showed "This kernel requires the following features not present on the CPU : PAE". I ...
3
votes
3answers
18k views

High CPU usage even when no application is running(Desktop)

I always have high CPU usage in Ubuntu in every version of it that I have used. I have been using Ubuntu from 10.04 version. My CPU usage even at idle is more than 30% for each core(unlike Windows 7 ...
3
votes
4answers
5k views

How to keep the laptop's temperature low without hardware cleaning?

Last few days I found out that when I open Google Chrome and the laptop's fans start working really hard and I can not touch the mousepad because of heating. I use Ubuntu 11.10 on my Toshiba A350-22z ...
2
votes
1answer
2k views

Why does CPU usage spikes to 90% and more after wake from suspend on Ubuntu 13.04?

On an Acer C7 Chromebook running ChrUbunutu (not CROUTON) I noticed a problem after moving to 13.04. If I put the system to sleep and then wake it up both CPU cores spike to 90%+ usage. Soon after ...
2
votes
1answer
600 views

Can i automatically kill any application that uses more than a certain percentage of the CPU and/or RAM?

What i need from my computer, now that it's summer at least, should never use a lot of resources - when applications do so it's because of some kind of bug or memory leak. Is there any way to ...
13
votes
4answers
6k views

Reinstall of OS after CPU Upgrade needed?

I recently upgraded my CPU from an Athlon II X2 250 to the Athlon II X4 610E(45W 4 cores -- can't beat the efficiency). Is an ubuntu reinstall required?
4
votes
2answers
2k views

Ubuntu 11 and 12 initially fast but later bogs down, CPU pegged

I started with Ubuntu 11 a few weeks ago. It's on a DELL M4300 with a OCZ SSD. Default setup, except that I've installed the proprietary NVIDIA graphics and BROADCOM wireless drivers. Dual boot ...
3
votes
1answer
175 views

How to update additional driver (Nvidia GPU and CPU)

Firstly i want my drivers up to date. So can you help me about that? And 1 more question, at CPU title we have 2 options like microwaves and do not use device. Which one i must use? I use that right ...
2
votes
3answers
7k views

higher cpu usage in ubuntu 12.04 than windows 7

Hi I have a Intel Core i5 with 6GB of Ram using ubuntu 12.04 64bit. I noticed that whenever I run chrome which is the faster browser for me in linux) when I watch youtube, the CPU usage for Chrome ...
1
vote
1answer
425 views

Kubuntu 15.04 very slow despite very high CPU usage for every task

It seems that every task that is run on my system uses an excessive amount of CPU power. Monitoring CPU use via conky or top, opening a page in Firefox or searching for something in google suddenly ...
1
vote
1answer
1k views

How do I boot Ubuntu in VirtualBox complaining that my CPU is incompatible?

After a long time spent with OS from boys from Redmont I would like to try something new. I decided to try some Linux editions, also Ubuntu Linux. I am completely new to this matter, this is also my ...
0
votes
1answer
2k views

TLP don't change CPU frequency

I check CPU clock speed with cat /proc/cpuinfo | grep "MHz", After sudo tlp start and sudo tlp bat still frequency is 2100MHz (Maximum). Could you please help me to solve this problem? I'm using ...
27
votes
7answers
28k views

Is it normal for compiz to consume 40% of my CPU with no other programs running?

When I have no other programs running, compiz takes up at least 40% of my CPU. Is this normal? If it is normal, is there anyway I could make this program take a smaller percentage?
9
votes
1answer
6k views

How to use cgroup in ubuntu 13.04

I'm trying to learn how cgroup works on Ubuntu and seems that cgroup doesn't work in Ubuntu 13.04. I am using the answer to this question How to set cpu limit for given process permanently. Cpulimit ...
9
votes
4answers
8k views

What can I do to prevent Ubuntu from overheating my Notebook?

I have an easynote tj65 (2.1 ghz dual core with Geforce GT240M) running Ubuntu 11.10 and Windows 7 in dual-boot-mode. While Windows 7 doesn't have any comparable issues, Ubuntu is making my notebook ...
10
votes
5answers
14k views

Dropbox is taking too much CPU time. How can I fix it?

I recently noticed that Dropbox is taking about 50-90% of my CPU for more than just a few seconds sometimes - mostly when downloading/syncing many or large files. Still, I guess that even when ...
5
votes
2answers
5k views

Fan speed high since upgrade to 12.04

Since I have updated to 12.04 LTS my desktop pc's fan runs permanently with high speed and is annoyingly noisy. CPU temperature is low. Here is what the sensors command gets me: nouveau-pci-0400 ...
5
votes
1answer
2k views

Lenovo ThinkPad L520 slows down when AC power adapter is plugged in

I have a new laptop Lenovo ThinkPad L520 (7859-5BG) Core i5-2520M(2.5GHz) with 4GB RAM. Having installed Ubuntu 11.10 32-bit, while browsing with Chrome on GNOME classic (no effects), I noticed 173% ...
4
votes
2answers
2k views

How to set governors for Intel to work as old good ondemand?

I used to work on my laptop on ondemand governor, which was switching CPU frequency depending on CPU usage. It worked quite nice for years and had three very important advantages: low hardware ...
4
votes
1answer
235 views

Which file is called or event is fired when we plug-in / plug-out power supply to the laptop?

Everytime I plug-in or plug-out powersupply the CPU frequency is changed to 'powersave' which results in reduced efficiency. I need to be on 'performance' all the time. I've made a small java utility ...
3
votes
2answers
637 views

Taking The Cores Offline

I have Intel® Core™ i7-2670QM CPU @ 2.20GHz × 8 process which has 4 physical cores and 4 logical cores. Most of the time i been on AskUbuntu, Watching videos, Basically no processor hungry ...
2
votes
2answers
5k views

Permanently change maximum CPU frequency

So far I've found temporary solution for my problem at Maximum CPU frequency stuck at low value, but the question that I have is how to make it permanent. Right after reboot, frequencies are set back ...
2
votes
0answers
1k views

After drop of Unity2D in 12.10: How to tackle high load of Unity/compiz on netbooks? [closed]

Update: Though it's not fully clear to me why this Q should be off-topic and I have doubts that a bug report will help, I filed a bug report at https://bugs.launchpad.net/unity/+bug/1067349 Please ...
11
votes
1answer
3k views

What is the mediascanner-service and how to avoid getting it installed?

Since a few months, on one of the desktop Ubuntu 14.04 systems I use, CPU has regularly been going up to 80-100% for no apparent reason. htop would usually attribute responsability to file system ...
7
votes
1answer
5k views

How to fix that only one out of four cores of my CPU is detected?

I have an Acer Aspire M5640/M3640 PC, featuring a Intel Core 2 Q8200 (Quad-core) processor running Ubuntu 12.04. Now it seems to only recognize just one CPU core. lscpu outputs: Architecture: ...
5
votes
3answers
2k views

CPU usage goes to 100% when I lock the screen

Whenever I lock the screen, after a certain amount of time, the CPU and the CPU fan go to their limits, and they return back to normal the moment I unlock the screen again (as shown by psensor). How ...
5
votes
1answer
6k views

Using quad core, but only 1 CPU entry in `/proc/cpuinfo`? Is SMP running on my computer?

I just upgraded my system and did a clean install of Ubuntu when I did (Installed Oneiric Ocelot from the CD last week but yesterday upgraded to 12.04 LTS). I have an i7 920 (quad core with ...
4
votes
1answer
5k views

How do I know my fan is working in Ubuntu

I just bought a brand new netbook and am worried the fan isn't working properly. lm-sensors does not detect a fan, I can't hear a fan, and can't feel air blowing out of the fan area. The netbook is ...
4
votes
3answers
676 views

ACPI 30k+ interrupts per second

My computer is currently doing something like 30k+ interrupts per second. This causes battery issues as well as the CPU being always stuck at the highest speed, making it very hot (overheating.. 75C ...
3
votes
1answer
4k views

How to really check current cpu Hz? [duplicate]

All programs I've tried seem to be listing Hz from cpu's specifications not actually checking what the current Hz really is. for example a processor is marketed with 4GHz.But this is the max (unless ...