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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60
votes
7answers
81k views

How do I get the CPU temperature?

How do I get the CPU temperature.
41
votes
7answers
83k 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 ...
35
votes
5answers
39k 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) ...
29
votes
4answers
14k 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?
22
votes
6answers
22k 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?
21
votes
3answers
42k views

How/Where do I check my ubuntu laptops's CPU usage?

How/Where do I check my ubuntu laptops's CPU usage? I want to check it but I don't know where.... Thank you
20
votes
2answers
2k views

Run program with only 1 CPU core

I'm trying to run a bunch of scripts related to a gaming server in Terminator. The only problem is when I do this, Terminator detects all my CPU cores and the PC lags. Is there any way to start it up ...
16
votes
5answers
118k 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 ...
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 ...
13
votes
2answers
23k 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 ...
13
votes
1answer
22k views

Adding a CPU monitor widget in the top corner like in Gnome2

I wonder if you can add a widget or something like it in the top corner (next to volume and WiFi and things like that) that displays current use of CPU and maybe RAM. I know you could add stuff like ...
12
votes
4answers
3k 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?
12
votes
2answers
1k views

Ubuntu 10.10 trash CPU overload

I have a weird bug with Ubuntu 10.10 on one of my computer. When I empty the trash, the process - gvfsd-trash goes to 200% and does not stop until I kill it (using kill -9). Does not matter if I have ...
11
votes
3answers
21k 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 ...
10
votes
2answers
3k 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 ...
10
votes
4answers
8k 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.
9
votes
4answers
7k 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 ...
8
votes
3answers
19k views

Why does kworker cpu usage get so high?

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 ...
8
votes
4answers
6k 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 ...
8
votes
1answer
5k views

How to control CPU fan with no pwm-capable sensors?

I've tried to follow the directions on this thread: How to control fan speed? But at the end of the day, pwmconfig gives me this error: /usr/sbin/pwmconfig: There are no pwm-capable sensor ...
7
votes
4answers
2k views

Is it possible to disable a CPU (not a core)?

Is it possible to disable a CPU, not a core? I want to do a test to verify if the performance could make a big difference or not. I'm using Ubuntu 10.10.
6
votes
5answers
8k views

High Idle CPU temperature under Ubuntu, but not Windows

I have a Dell Inspiron Mini 1012 running Ubuntu 10.04 and Windows 7 Starter in a dual-boot configuration. The CPU runs much cooler in Windows than it does in Ubuntu, even when the CPU has been ...
6
votes
1answer
2k 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 ...
6
votes
1answer
2k views

How to control CPU frequency

On Lenovo T400 and Ubuntu 10.10, I am using CPU Frequency Scaling Monitor 2.30.0 on the panel to show and control CPU frequency. My CPU frequency by default will change according to load. But I want ...
6
votes
1answer
1k views

High CPU when I open nautilus

Everything else works fine but when I open my home folder or move stuff around in it my cpu gets really high and everything slows down. This started to happen after upgrading to 11.10. Everything in ...
6
votes
2answers
676 views

Can't start Ubuntu - Package power limit notification

I used Ubuntu 12.10 on my current laptop for a couple of weeks without problems... Now there is no way to start it. When I try to boot Ubuntu during the startup process I get this error: [CPU0]: ...
5
votes
2answers
12k views

How do I monitor CPU core usage per thread?

I need this information to optimize the number of worker threads my custom application is allocating. For example, if I just use top on a single-threaded application on a two-core machine, the 100% ...
5
votes
1answer
457 views

Much lower temps on Ubuntu [closed]

I've noticed that CPU temps and GPU on my laptop are much lower on Ubuntu than Windows 7. On Windows temperature is like 50 celsius to 58 and on Ubuntu 40 to 50 max. Cooling is also much cooler on ...
5
votes
4answers
7k views

watchdog/0 process using all my CPU suddenly

I have a fresh installation of Ubuntu 12.04, I have been running it for about a week. Suddenly today I noticed my computer freezes every 5 seconds. I restarted the computer and I still get this. I ...
5
votes
1answer
1k views

How to make “R” use all CPUs

I am using GNU R to calculate a huge dataset. My PC has 4 CPU-cores, and I can see, that R is using only 1 CPU. Is there a way to tell R to use all 4 CPUs in order to make the calculation complete ...
5
votes
1answer
1k views

How can I check if my computer has AES-NI support?

I've heard that disk encryption works reasonably faster when CPU supports AES-NI. How can I check if my CPU supports it? Does the Ubuntus default encryption (dm-crypt) use it by default or do I have ...
5
votes
2answers
626 views

fancontrol on no pw-capable machines

I've installed Ubuntu 13.4 on my Alienware m14x and noticed one thing, cpu gets as high as 70 degrees centigrade (with nothing resourceful running) and cooler doesn't respond to that, just stays calm ...
5
votes
2answers
4k 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% ...
5
votes
4answers
12k 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 ...
5
votes
1answer
2k views

How do I read CPU temperatures on a Phenom II processor?

I am trying to measure the temperature of the CPU cores on my latest ubuntu 11.04 install with kernel 2.8.32 to no avail. I have followed the instructions at ...
5
votes
1answer
153 views

What can I change/investigate where the install does not complete?

I have already successfully installed Ubuntu 10.10 on my laptop and it works fine. I attempted to get my desktop PC to dual boot Windows and Ubuntu but found that neither the 32 or 64 bit install ...
4
votes
1answer
7k 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 ...
4
votes
1answer
117 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 ...
4
votes
2answers
460 views

How can I diagnose what process is using CPU time?

It's a "problem" that i have since 11.10, now I've upgraded to 12.04 (fresh install). Even while ondemand governor is set, and the computer is idle, fan goes on and doesn't want to shut down. Images ...
4
votes
4answers
6k views

100% CPU usage in Ubuntu 11.10

I recently installed Ubuntu 11.10 with Unity to dual boot with windows 7 on my lap top. My laptop is running an Intel i7 quad-core and 8gb of RAM just as some background. I've noticed that when I'm ...
4
votes
3answers
2k views

How do I analyze my CPU usage over a long period of time?

I am just wondering if there's any Ubuntu app that can track my CPU usage. The problem is that I am currently using a quad core i5, whilst what I do most in daily usage is just browsing and rails ...
4
votes
1answer
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 ...
4
votes
1answer
4k views

Difference between core temp and cpu temp

I installed a sensor reporting utility on my Ubuntu machine (a desktop machine) and it reports drastically different temperatures for the ACPI CPU reading and the ISA Core 0/Core 1 reading. The ACPI ...
4
votes
1answer
2k 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: ...
4
votes
2answers
4k views

How can I lower the CPU temperature?

I have installed Ubuntu 12.04 on my EeePC 1015PX and I've noticed that the CPU temperature does not go below 60ºC (70 is usual). Looking at powertop it seems the 2 cores (Atom N570) are idle most of ...
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 ...
4
votes
3answers
532 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 ...
4
votes
1answer
276 views

How to automatically slow CPU instead of starting fans?

In Windows' power options, you had the ability to configure your system to use either 'active' or 'passive' cooling schemes. In the 'active' scheme, the fans would start running faster as the CPU got ...
4
votes
3answers
4k views

Dropbox very high CPU usage without any actual data transfer

The Dropbox process constantly clocks more than 50% CPU usage sometimes going up to the higher 80s and 90s. At the same time it does not even upload/download the files it is supposed to. The progress ...