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

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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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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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481 views

Simple way to compare processors

Today, comparing processors is obviously not just looking at the frequency and the number of cores. When choosing a new PC, how do you compare processors? Is there some resource, like a site or ...
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How to fix the “Firefox using max CPU” problem?

Every now and then while browsing, my Firefox CPU usage shoots up to the max possible (that's 50% for my dual processor laptop). It remains at max usage even when I close all the tabs. In fact, the ...
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4answers
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Multi-core CPU: can I say I have a 3x2.1GHz=6.3GHz CPU?

I have an AMD A6-3500 three-core CPU. AMD System Monitor shows each core with a maximum 2100 MHz. This also shows in AMD OverDrive. Does this processor run at the speed 3*2100 MHz? Edit Can I say ...
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Processor not running at max speed

My laptop has an Intel Core 2 Duo T9300 which should be running at 2.5GHz, however CPU-Z consistently reports my Core speed at right under 1.6Ghz (8x multiplier and ~200MHz Bus Speed). Even when I'm ...
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5answers
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Whats the deal with these new lower clock speed CPUs on Laptops? Can they still run apps well?

I'm looking at some new laptops, and I'm seeing the AMD Neo CPUs at 1.5GHz, and some of the new Intels at 1.3-1.8GHz. The laptops they are on come well supplied in terms of RAM (up to 8GB) and Video ...
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Why have CPU manufacturers stopped increasing the clock speeds of their processors? [closed]

I have read that manufacturers stopped concentrating on higher clock speeds and are now working on other things to improve performance. With an old Desktop machine with Intel® Xeon® Processor E3110 ...
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6answers
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How does the CPU and GPU interact in displaying computer graphics?

Here you can see a screenshot of a small C++ program called Triangle.exe with a rotating triangle based on the OpenGL API. Admittedly a very basic example but I think it's applicable to other ...
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4answers
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How to set processor affinity on OS X?

How do you set processor affinity in Snow Leopard on a MacBook Pro?I know in Windows you could just switch it in Task Manager.
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4answers
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Is the CPU active in Sleep mode?

Suppose on a Windows OS, you toggle the computer to go into sleep mode and put it away. As far as I know there will no programs or processes will be running. But would the processor still be running ...
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2answers
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Linux: command to know the processor number in which a process is loaded?

Is there any command in linux to figure out , given a process, which processor the process is running? I am interested in figuring out the CPU busy and CPU idle time of that processor.
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5answers
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Why can't you have both high instructions per cycle and high clock speed?

The Megahertz Myth became a promotional tactic due to differences between the PC's INTEL 8086 processor and Apple's Rockwell 6502 processor. The 8086 ran at 4.77MHz while the 6502 ran at 1MHz. ...
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6answers
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What regulates Intel SpeedStep CPU throttling? Can I get some control of this on Windows7?

I’m trying to get a big virtual disk file compressed (using WinRar) before I go home today, but my CPU frequency keeps merrily going up and down between the nominal 2.8 GHz and a measly 800 MHz! The ...
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2answers
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Maximum CPU Temperature for Core 2 Duo E6400

What is considered to be the highest safe CPU temperature when overclocking? I have a Core 2 Duo E6400 overclocked to 2.85GHz with 1.2vCore. This runs at 29C idle and 45C under load. These ...
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7answers
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Why are modern CPUs “underclocked”?

I keep reading since years about magical overclockability of modern CPUs. It is said that CPUs (with open multiplier) which are shipped to customers with (let's say) preset 3GHz, can be overclocked "...
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2answers
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Upgrading laptop RAM [duplicate]

(This question was originally asked for my specific laptop: Dell XPS 15 L502X. But it seems that understanding I gained from the upgrade experience I am able help my friends to decide upgrading RAM ...
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6answers
8k views

Why is Google Drive so heavy on my CPU?

As the below screenshot shows, despite the fact that Google drive doesn't appear to be doing anything (it's not syncing any data) it's using over 12% of my CPU (a core i7). The official ...
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2answers
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How does Intel Turbo Boost work?

I just got a new Intel CPU, and the specifications say 3.5GHz but with turbo boost to 3.9GHz. What does Intel Turbo Boost do? From the description it sounds like they are saying "The road's speed ...
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1answer
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What does CPU usage for a process actually mean

Assume the computer has a single core - what exactly does it mean for process A to be running at 100% CPU capacity vs (lets say) 10% CPU capacity. If the CPU was 2.0 GHz, does that mean in a time ...
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4answers
8k views

VirtualBox CPU usage 100% on host [closed]

I have installed VirtualBox 3.1.2 (latest) on my Windows 7 (x64). In the VirtualBox I've installed Windows 7 (x64). I have 4 GB RAM installed. The guest has been assigned a 1536 MB RAM. Sometimes the ...
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2answers
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Safe long-term CPU temp? [closed]

I'm considering running a game server for some friends and I to play on with my laptop, but while the server is running my processor use tends to go to around 55-65% and my CPU temperature hovers ...
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8answers
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Should I choose 32 or 64 bit for Linux?

I own a Linux workstation which currently has 4 GB of RAM and planning to go for 8 GB in the near future. CPU is a Core2Quad Q9550. Should I install a 32 or 64 bit variant of Linux?
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3answers
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Can a single-threaded program be made to use multiple cores?

The title says it all: is there a way to get an older program designed to use a single CPU core to use multiple CPU cores?
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1answer
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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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1answer
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How do I get AVX support in QEMU?

I want to play with the new AVX instructions. I saw that QEMU might have support, so I built it from Git (yesterday). I set the CPU to SandyBridge and I booted Tiny Core Linux. TCL has kernel 3.0 and ...
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Is my i7 CPU running too hot?

Here's my setup Intel i7 940 - stock speed 12GB DDR3 RAM ATI Radeon HD 4800 Series 2x 10k RPM Velociraptor Hard drives At no load, room temperature my cpu cores consistently read: 43 43 46 43 (...
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5answers
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Is the cache size or number of cores more important when weighing CPU performance?

I'm shopping for a laptop for my son to use for school, so it doesn't need to be a gaming machine. I've put together PC's from scratch before, but it's been a while. I've noticed that a number of ...
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4answers
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How to see if turbo boost is working on I7 860 CPU?

I just build myself a new system with a Intel I7 860 CPU. When loading it using a single threaded application like Super PI, CPU-Z shows 2.933Ghz as speed. Now I understood that the I7 goes into turbo ...
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1answer
4k views

Why do we need multiple levels of cache memory?

In general a cache memory is useful because the speed of the processor is higher than the speed of the ram (they are both increasing in speed but the difference still remains). So reducing the number ...
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5answers
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Are there seperate processors for Servers?

To my knowledge a Server PC and a desktop PC can have the same processor. But someone told me Servers are equipped with more powerful Processors (that is these processor are designed for Servers only)....
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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 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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5answers
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How do I read Intel CPU specs?

Intel® Core™ i7-640M (2.8~3.46GHz, 35W) w/4MB Cache - 2 Cores, 4 Threads - 2.5 GT/s SO i'm buying a new laptop, which i have not done in 6 years. So i am not familiar with any of these cpu specs. It ...
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2answers
480 views

Is there any way to see what my CPU is doing at the “assembly level”?

I was looking at how Assembly Language works, because I want to learn how the complex and fancy things my computer does actually happen at the CPU register/hardware levels. Is there any way to see ...
3
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3answers
327 views

What's the relationship between CPU, RAM and performance?

I have an HP EliteBook Folio 9470m with an Intel Core i5 processor at 1.9GHz and 4GB RAM. Is it useful to buy an additional 4GB RAM memory with this CPU? Or would the extra RAM be wasted from a ...
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2answers
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Instruction per Cycle vs Increased Cycle Count

Increasing either instruction per cycle or increase cycle count both are valid design choice for processor manufactures. I understand theory, but it would be much clearer if I had some real life ...
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Why would my computer all of sudden reset clock, show new boot screen, and run fans loud?

I bought a new computer one year ago, it's worked fine (Windows 7). A few months ago, it started to not boot unless I removed my USB headphones connected to a USB hub, everything else worked fine. ...
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4answers
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How to control the processor frequency of i5 in Windows 7?

On Ubuntu I can control the frequency of my CPU. I set it at the lowest value and then the fans are really quiet. Is it possible to do it in Windows 7 ? EDIT: The computer is a Laptop: Sony SVT 1311
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1answer
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Curios: What makes CPUs better than others? [closed]

I have been wondering about this for a long while now and was hoping someone here could answer it pretty easily. If I was looking for the most powerful CPU what should I really be looking at? There ...
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1answer
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How to allocate more processor power to my (Ubuntu-based) Virtualbox system in Windows 7?

I have installed an 32-bit Ubuntu based Linux OS, Elementary, on a VirtualBox installed in Windows 7 (32 bit) , on a 64-bit laptop which has a 2-core Intel i3-2330 CPU @2.20Ghz, and 4GB RAM (2.45 ...
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CPU Fan is Loud, but the Temperature is OK (I Think)

I recently find that my CPU fan is getting louder and louder. It is now so loud that I bother to type up a question on it. The first thing I check is the temperature using Core Temp, it seems that ...
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CPU usage jumps to 100% -> WHEN <- machine is idle (not the idle process) [duplicate]

Possible Duplicate: Task Manager shows 100% CPU utilization, but nothing in process list does. My friend has a machine in his teashop that I am attempting to troubleshoot, so far with minimal ...
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2answers
6k views

Does a motherboard have to support 64-bit or is it just the CPU?

Do I need to have both components to support 64-bit, motherboard and CPU. Or is it just the CPU that matters?
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1answer
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Ubuntu: AMD64 vs i386?

I cant understand what these are even though I've read articles about them. Does it have something to do with 32 bits and 64 bits CPU? so why is it saying "AMD"64 and "I386"? AMD is a label just ...
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How fast is each core in a dual-core processor?

My Macbook has a 2.4 GHz dual core processor. Because it has two separate cores, that means it can execute two functions at once, right? So does that mean each core is approx. 1.2GHz each (for a ...
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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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CPU makes an electric leak like sound

For a while my computer have been making a electric leak like sound whenever the CPU usage gets high. However, lately it started to make it more often. For example with anti-virus searches and malware ...
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Why does my Intel CPU underclock itself automatically?

I have an Intel i3 350m and a Core 2 Quad 8300. The 350m is 2.2ghz, while the Core 2 Quad is 2.5ghz. With both, while looking at CPU-Z, they underclock themselves at seemingly random intervals (even ...
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Which property of CPUs is good for what?

Back in the days clock frequency used to be THE criteria to compare CPUs (or perhaps you had to take into account whether it was a DX or SX). The world was simple back then, but in these fast evolving ...