A CPU (Central Processing Unit) is the chip responsible for actually "doing" most the instructions given to a computer.

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What are the common causes of CPU failure?

What are the most common causes of CPU failure? Are there intermediate states between a perfectly functioning CPU and a dead one?
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Difference Between Cores and Processors

I am confused by the difference between "Cores" and "Processors". A lot of the computers are 2-cores, 4-cores. Does this mean that they have one processor, but with 2 or 4 cores on that single ...
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Interpreting output of cat/proc/cpuinfo

How does one interpret the information printed out by the following command in Linux cat /proc/cpuinfo On my laptop, I get the following output: [gaurish108:~]$ cat /proc/cpuinfo ...
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Why is my CPU usage broken in Process Explorer?

On my system (Windows 7), it seems that Process Explorer is reporting the wrong CPU usage: When Firefox is running, I constantly get 30%+ When I kill Firefox, I still get about the same CPU usage ...
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Wild CPU temperature fluctuations during stress test

I have upgraded my laptop CPU and gave it a stress test. The weird thing is that during the test the CPU temperature readings fluctuate wildly in a periodic manner. At idle, the CPU temperature is ~45 ...
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How does hibernation work?

I'm wondering how hibernation works. Obviously it writes the contents of RAM to disk, but is there anything else? does it save/restore CPU state? cache state? anything else?
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How do general binaries take advantage from new instructionsets on new CPUs

With every release of a new processor, there are changes to the instructionset the processor supports. For example, Haswell has Advanced Vector Extensions. However, when I run a program on a PC with a ...
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How to have Microsoft Virtual PC use 2 CPUs

I have XP mode running on Windows 7. How can I setup multiple CPU usage (to boost performance)?
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Single Quadcore or Dual Dualcore?

If you have to choose (everything else being equal) between one processor with four cores, and two processors with dual core, what are the points in favour of each solution?
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Does the 6502 put FF in the stack pointer register as soon as it gets power for the first time?

I'm reading about the 6502 processor's instruction set from the many links at 6502.org, and one tutorial states: The stack pointer (S) points to a byte on Page 1, that is, to a byte whose address ...
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What is the impact of running the CPU at 100% for long periods at a time? [duplicate]

Possible Duplicate: Is it ok to have 100% CPU usage constantly I recently upgraded computers and with this upgrade I decided to try Seti@Home to run in the background. I was watching the ...
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Setting CPU cores off-limits to all threads not specified (preferably in Windows 7)

I have a really specific machine configuration in the works that would really be helped out if there were any way to do this...basically what I'm looking for is the opposite of setting CPU Affinity ...
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Dropbox causes high CPU usage on Mac OS X 10.8.2 (Mountain Lion)

Dropbox will occasionally use around 100% of the CPU. Why is this happening and how do I fix it? From searching around, it seems like it's not an uncommon problem.
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Can I increase the L2 cache memory of my CPU?

I noticed that my laptop seems to have 4x the amount of "L2 cache memory" than my desktop, is that normal? laptop: Intel Core Duo CPU T2450 @ 2.00GHz, L2 cache memory 2 MB, system bus 533 MHz ...
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What determines endianness

I was wondering if endianness only depends on CPU? Does it depends on other hardware, such as memory, secondary storage device? Does it depends on OS? Why in Wikipedia, does it seem to be true? ...
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What affects installation speed?

Super hardware noob here. My wife and I were installing a game on our laptops last night, from an installation file (not a disc). The game takes up about 7.6GB of HD space. My laptop installed the ...
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Can someone clear up the terms Core Duo CPU, Quad Core, Dual CPU, etc.?

I'll be buying a new computer in the next couple months and want to understand the dual/duo/two CPU issue: Core Duo CPU (is this one "duo" CPU or two? Quad Core (four cpus?) Dual CPU (two cpus?) 2 ...
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Mixing CPUs in a multi-CPU system

Mixing types of RAM is not always healthy, but I am curious as to what happens (if anything) when mixing CPU types in a system. Example: 8-Core 2.0Ghz Magny Cours CPU in socket 0 12-Core 2.0Ghz ...
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How can I determine whether my processor is 32-bit or 64-bit?

How can I determine whether my processor is 32-bit or 64-bit? My processor is AMD Phenom 8450 triple-core.
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CPU temp very hot in BIOS but okay in RealTemp/Speedfan

I just built myself a new i7 2600k system with an Intel DP67BA motherboard. Booted into BIOS and was alarmed to find Processor temp reported at 75 C, and steadily rising... sat there while it rose to ...
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AMD CPU Equivalents

Could someone clarify the following: Intel Core 2 Core 2 Duo Xeon Xeon Quad Core Core i7 What would the AMD equivalents be? I have no particular reason for asking, I'm just curious.
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Can keeping my CPU speed at “high performance/turbo” all the time decrease its lifespan?

Can keeping my CPU speed at “high performance/turbo” all the time decrease its lifespan? And if so, what would be its expected route of failure if it does happen?
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How to unglue microprocessor from heat sink?

I disassembled a Dell Precision 530 and replaced 5! bad capacitors. I tried to reassemble it but realized that I cannot succeed unless I can remove the microprocessor from the heat sink. The ZIF ...
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Upgrade motherboard and CPU without reinstall

I have a home server running Ubuntu 10.04. I want to replace the motherboard and CPU without reinstalling the OS. I read a long time ago that this would sort of work on Windows XP, but with stability ...
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Can I reduce the CPU speed of my MacBook when on battery?

I've got a MacBook with a Core 2 Duo CPU. I've got CoreDuoTemp installed which can show the current speed of the CPU. It appears to always show: Mini : 1.0 GHz Maxi : 2.0 GHz Current : 2.0 GHz I ...
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How is a byte(s) loaded from a secondary-storage device in to RAM upon bootup, if RAM supposedly already contains bits in capacitors?

This has been on my mind today. If RAM's ICs contain bits stored in capacitors sitting there, how can you pull bits from somewhere and put them where something already is? For example, on bootup, ...
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Intel Pentium D & Intel Core 2 Duo

Are the Intel Pentium D and Intel Core 2 Duo processors the same?
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How to slow down my CPU?

I have Vaio Z-690 laptop, and its processor speed is 2.66 GHz. I don't need too much speed, and I'm OK with 2 GHz or even less. Just for browsing websites it's enough. I want to slow down ...
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What is a processor cache?

I recently downloaded CPU-Z just to check things out, and saw a tab marked Cache on it. It shows what appears to be different memory sizes, and I have seen processors being advertised with an X sized ...
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Quad cores have lower processor speed, are they still better?

So, I am looking at building a new laptop. Two examples of the processors I am looking at are: Intel® Core™ i7-740QM Quad Core 1.73GHz 6MB Intel® Core™ i5-520M Dual Core 2.40GHz 3MB Now I realize ...
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Why SRAM is faster than DRAM?

In modern multi-core processors, the processor caches (L1,L2 and L3) are made up of SRAM with decreasing speeds(L2 caches are higher speed SRAM than L3 caches which is a cost trade-off). The main ...
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How far do electrons physically move in a single clock cycle in a (theoretical) 4GHz processor?

I was musing last night about computers and processors and this video of a 6-bit digital adding machine, and I know that 4 GHz seems to be the practical limit of mass-produced CPUs of the current era. ...
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What does the MHz of RAM really mean?

Countless of times I've heard and read that RAM-memory can have different speeds - denoted as MHz (e.g. 1066 MHz). However, what this frequency really is has never been explained to me and I'm having ...
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How does Intel Turbo Boost Technology improve performance on the new Core i5, i7 series of chips?

I'm curious about the new innovations in Intel's Core i5 and i7 series of chips, in particular the Turbo Boost Technology. (Doesn't turbo boost remind you of Knight Rider?) What are the details on ...
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Is disabling graphics driver and falling back to CPU for graphics processing a good solution?

I bought a Sony Vaio VGN-FZ50B notebook in Japan about 5 years ago. About a year ago I updated my operating system to windows 7, but I couldn't find a version of drivers for my graphics card for my ...
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What does the numbers and figures listed on Processors stand for? [closed]

if you look into current Intel processors then you would notice number of things, few are as below. i3, i5 and i7. What does their name stands for. Sandy bridge and Ivy bridge Some figures ...
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Intel data bus of Intel 80486 and above CPUs

Why do Intel 80486 and above CPUs have a double 32-bit internal data bus? ALU is still 32 bits wide, so what is the extra 32-bit bus for?
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Kernel and User mode distinguishing

Who is responsible for determining that the process is in the Kernel mode or User mode? I know kernel knows which process is belong to what space, but how the CPU determines that? I mean should CPU be ...
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What happens when too much thermal paste is used

A client of mine brought in a computer he wanted to get cleaned up, OS reinstall, and had a video card in hand he wanted me to install... no big deal. So I open up the case and see this... Wow, ...
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Windows 8 generates less heat than Windows 7?

I have a dual boot with Windows 7 and Windows 8 Professional on my laptop. When running Windows 7 on my laptop, the CPU core temperature usually ranges from 42°C to 47°C. However, when I run ...
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How is the percentage of CPU usage calculated?

In my Ubuntu 12.04, with psensor, I saw a percentage number updated for cpu usage. I wonder how this percentage caculated? Specifically, what is the numerator and denominator in the ratio? Thanks!
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Windows 8 Release Preview - Extremely High Idle CPU Usage

Using Windows 8 RP, my computer is sustaining a 26.6% CPU usage while sitting at the desktop doing absolutely nothing. The other day it was over 50%. The entire usage is due to a process called ...
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How to find a flops of a CPU?

I'm using Intel Xeon CPU x5660, 2.80GHz 2.79Ghz in a computer. I'm trying to find the FLOPS of the CPU, have searched on Internet but didn't find anything about it. Does anybody know how can I find ...
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System and Interrupts causing high CPU

Under Process Explorer, I noticed that System -- and occasionally Interrupts -- are taking between 5% and 20% CPU constantly, for hours on end. This is resulting in weird video playback problems. ...
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How did the Cyrix 586 chip work in an Intel 486 computer?

When I was a kid we had a 486 DX, 33mhz machine. Pretty sweet eh? Well as it got older we tricked it out, added 8 megs of ram so we could place Space Quest 6 and an 2x External CD-Rom drive etc... I ...
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Setting permanent process CPU core affinities in Windows

I am planning on getting a new CPU and am looking at a quad core i5. The reason for the quad-core is that I generally multi-task a lot for example running Visual Studio, Eclipse Aptana, Photoshop, ...
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What steps do you take when overclocking?

When overclocking your system? what steps do you take to get a maximum but stable overclock out of your system? I've personally just slammed up the FSB speed until my system can't run Prime95 for a ...
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The meaning of thermal throttle counters and package power limit notifications in Linux

Whenever I do some performance testing on my Linux-installed MacBook Pro, I often see the following messages in dmesg: Aug 8 09:29:31 infinity kernel: [79791.789404] CPU1: Package power limit ...
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Chrome uses 100% cpu on youtube after update

Chrome 40 is using 100% cpu when playing youtube videos full screen My CPU is core i5 @ 2ghz with intel 4400 gfx card. it should be able to play them and I dont remember having this issue b4 Chrome ...
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Why would my CPU suddenly get much hotter than it used to? [closed]

I run an i7-2700K on a DZ68BC, which I've assembled about a year ago. I've used the stock Intel fan without additional thermal compound and it worked flawlessly ever since. I've had the Intel Desktop ...