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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40
votes
7answers
80k 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 ...
55
votes
7answers
73k views

How do I get the CPU temperature?

How do I get the CPU temperature.
34
votes
5answers
35k 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) ...
8
votes
3answers
18k 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 ...
16
votes
5answers
114k 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 ...
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?
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 ...
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 ...
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 ...
13
votes
2answers
22k 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 ...
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.
3
votes
3answers
854 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. ...
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
417 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 ...
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?
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 ...
2
votes
3answers
6k 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
879 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 ...
22
votes
6answers
21k 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
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 ...
7
votes
3answers
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 ...
11
votes
3answers
20k 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 ...
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% ...
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 ...
4
votes
3answers
525 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
0answers
2k views

Fan always on and overheating problems on HP G62

I have a HP G62 with i5 processor, 4G Ram and ATI HD 5470. Started using Ubuntu 4 months ago, first was 11.10 and after 12.04. Everything worked perfectly until some weeks ago when my cpu fan became ...
3
votes
1answer
4k 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 ...
3
votes
3answers
6k views

Overheating problem on Ubuntu 13.04

I have recently upgraded Ubuntu to 13.04. Since this time I have overheating problems with CPU and graphic card. I also can't use fglrx drivers, because Ubuntu does not work properly, so I use the ...
3
votes
1answer
2k views

Why is Ubuntu detecting only one processor core?

My processor is Intel P6100 which is a Dual Core processor. When I do cat /proc/cpuinfo this is what get varun@varun-K52F:~$ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu ...
3
votes
4answers
12k 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 ...
2
votes
1answer
2k views

Is there a way to change the speed of a CPU fan?

I got a more powerful CPU and can see from the system load applet that whenever the CPU has got some work, the fan turns up very much. It's much louder than before even if the CPU was working hard. ...
1
vote
1answer
872 views

Macbook 8,1 Ubuntu 12.10 CPU Heat

Installed Ubuntu on another partition on my Macbook, which works well sorted the wifi but the problem is that the heat coming off the thing is mental. The fans are going to cool it, and i have ...
1
vote
0answers
268 views

When I kill Xserver it causes a random process, usually compiz, to use 100% of a cpu core [closed]

I don't have any more clues , unfortunately Every time i force a logout (control-alt-backspace i mean) and login again, a random process uses 100% of a cpu core, usually compiz or nautilus
0
votes
1answer
79 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 ...
0
votes
0answers
157 views

100% I/O usage due to jbd2

I have 14.04 Beta 2 64-bit and Intel i7 Processor with 2.2Ghz clock, 4 GB RAM and 500 GB Harddrive. After using Ubuntu for some time, everything goes so slow and I cannot even move my USB mouse ...
0
votes
2answers
5k 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 ...
0
votes
1answer
4k views

Ubuntu 13.04 - High temperature [duplicate]

I've always used Ubuntu. I installed the version (13.04) and I have a problem: the CPU's temperature is high also in normal condition. This is the response of lm-sensors: acpitz-virtual-0 Adapter: ...
0
votes
2answers
3k views

Ubuntu 12.04 high CPU usage and high temperature

Ubuntu 12.04 on my laptop uses more than 50 percents of each core even if nothing is running. I have checked from system monitor and from htop, both of them show that each of 4 CPUs percentage is ...
0
votes
3answers
522 views

CPU Frequency is off

I'm working on overclocking my rig right now, but I need to know the cpu frequency from within Ubuntu. I've figured out that I have to run a stress test while preforming the following commands to get ...
0
votes
3answers
5k views

How to change CPU fan speed on ThinkPad?

I checked this post on AskUbuntu, but like the OP my BIOS does not have a setting for 'smart fan'. My BIOS though has something similar called 'Thermal Performance' wherein it's already set to maximum ...
0
votes
2answers
748 views

Why I get non-symmetric usage of CPU on multicore PC

CPU: AMD Phenom II X4 955 Ubuntu 11.10 amd64 I launch some application that use only one core and when I look at cpu-load graphic in gnome-system-monitor I found that all of my four CPU's loaded not ...
0
votes
3answers
1k views

Installing 64bit ubuntu on Intel(R) Core(TM)2 Duo CPU T5870 , possible?

I'm thinking if it's possible to use a 64bit ubuntu on a dual cpu architecture ? How can i tell from /proc/cpuinfo ? processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model ...