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

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If 32-bit machines can only handle numbers up to 2^32, why can I write 1000000000000 (trillion) without my machine crashing?

32 bit computers can only store signed integers up to 232 - 1. This is why we have run out of ipv4 addresses and have entered the 64 bit era. However, the number 232 - 1 (2,147,483,647) is not as ...
212
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12answers
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Why are we still using CPUs instead of GPUs?

It seems to me that these days lots of calculations are done on the GPU. Obviously graphics are done there, but using CUDA and the like, AI, hashing algorithms (think bitcoins) and others are also ...
146
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15answers
17k views

Is the performance of a CPU affected as it ages? [closed]

This is a hypothetical question about how a CPU operates. If I purchase two identical CPUs, and use one long term (say one year), will it be identical in speed to the unused CPU? Will the number of ...
101
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5answers
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What is the difference between an Intel i7 and a Xeon quad core processor?

I know the Xeon processors have been around for a long time and are mostly used in servers, but I am curious, why do people not use the Xeons in a high performance desktop? As far as I know about ...
88
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13answers
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Why doesn't “add more cores” face the same physical limitations as “make the CPU faster”?

In 2014, I hear a lot of programming languages touted for their concurrency features. Concurrency is said to be crucial for performance gains. In making this statement, many people point back to a ...
64
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6answers
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How can I monitor the CPU temperature under linux?

How do I monitor and display the CPU temperature using Linux?
63
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8answers
6k views

What's the difference between mobile and desktop processors?

I just read about the new Samsung Galaxy Note Edge having a 2.7GHz quad-core processor and 3gb of Ram. The laptop I bought last year by HP is 4 Gb of ram and 2.3GHz quad-core and my iMac is even ...
62
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8answers
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How can I check the temperature of my CPU in Windows?

Does Windows provide a means to check my CPU temperature natively? If not, are there any software tools which can reveal this information?
57
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6answers
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How does a CPU 'know' what commands and instructions actually mean?

How does a processor 'know' what the different commands mean? I'm thinking of assembly level commands like MOV, PUSH, CALL, etc...
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9answers
8k views

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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14answers
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Why are they putting “processors” on hard drives?

What does it mean when hard drives have a processor on the hard drive? How does it work, and what benefit does it have? I don't understand - the CPU on the computer is the processor and the hard ...
47
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5answers
8k views

Why is my dual-core CPU recognized as a quad-core one?

My processor is an Intel Core i3-380m. As you can see, it's 2 cores and 4 threads. Although, both Ubuntu 11.04 and Windows 7 seem to think it's a quad-core CPU: Why is this? Is it because there ...
46
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5answers
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Is it dangerous to run a CPU in an extremely cold environment?

We are in a fish processing unit where the temperature is constantly at -10°C (+13F). If we use a machine in here, will it be at risk of damage from the cold? Is there any considerations we need to ...
44
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12answers
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CPU Cores: The more the better?

I currently have a dual-core processor at work and a quad-core at home. I've noticed both PCs are pretty equal as far as launching applications/surfing the web. The difference I can see is that my ...
37
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7answers
112k views

How to tell how many CPUs (cores) you have on Windows 7

I got me a nice new laptop and I want to know a bit more about the hardware. How can I see how many CPUs my computer has in Windows 7? (Note: Clicking on Start->Right clicking on Computer-> ...
33
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6answers
17k views

Is it OK to use toothpaste instead of thermal paste when fitting a CPU?

I was told many years ago to do this by someone who at the time knew more than I did. The CPU was a celeron in the Pentium 2 era. It ran cooler with the toothpaste between the chip and the heatsink ...
31
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7answers
9k views

Has CPU speed already broken Moore's law?

I remember sometime around 1995 having a computer with CPU speed of 75 MHz. Then a couple of years later around 1997 having one that was 211 MHz. Then a few years later around 2000 having one that ...
31
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5answers
4k views

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. ...
30
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14answers
5k views

Removing the CPU while the power is on [closed]

What will happen if I remove the CPU while the power is on? Does anything happen to the computer? Has anyone tried this?
30
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5answers
8k views

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 ...
27
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6answers
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How many cores I am using on a Linux Server?

I am just wondering how I can find out in bash how many CPU cores a user is now using on a Linux Server? I am submitting a fair amount of background jobs to the server, so I'd like to write a bash ...
27
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8answers
3k views

Where does power consumption go in a computer?

Today we had a weird discussion over lunch: What exactly causes power consumption in a computer, particularly in the CPU? (ETA: For obvious reasons I don't need an explanation why a hard drive, ...
27
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4answers
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Are CPUs more stable with one or more cores disabled?

I was reading this article, and I couldn't help noticing this: ...7003.38 MHz, with two CPU cores enabled and hyper-threading disabled. Does disabling some CPU cores & disabling ...
26
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2answers
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Hyper-Threading and Dual-Core, What's the Difference?

In a conversation with the network administator, I mentioned that my machine was a dual-core. He told me it was not. I brought up the task manager, went to the perfomance tab, and showed him that ...
25
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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 ...
25
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4answers
2k views

Very high-pitched noise when computer does something intense?

"Intense" is the best word I can use to describe it because I'm not sure what it is, whether it's RAM, GPU or CPU. If I pan the camera in unity: A high pitched noise issues from the computer. The ...
24
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3answers
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Are there solutions that can limit the CPU usage of a process?

I am using an old laptop and doing heavy processing that needs high CPU usage for a long time (~30mins - 2hours). When the process puts heavy load on CPU for a long time, CPU overheats and computer ...
23
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4answers
3k views

Fake Intel CPUs?

I recently purchased a processor off eBay that was labelled as an Intel Core i5-2520M. It came shipped in just a tray, not the original box, but the processor and all its markings look perfectly ...
20
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9answers
2k views

Why aren't CPUs bigger? [closed]

CPUs are relatively small, and engineers are constantly trying to make them smaller and get more transistors in the same surface. Why aren't CPUs bigger? If an approximately 260mm2 die can hold 758 ...
20
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2answers
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x86 vs x64 - Why is 32-bit called x86? [closed]

Presumably the x86 was called so because the machines used 80386 and 80486 processors. Is that correct? Is that the right way to refer to 32-bit and 64-bit machines?
20
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4answers
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Any way to tell apart a CPU defect from a mainboard defect?

I have a fairly modern desktop computer, an AMD Athlon II X2 based silent PC, that does not work. When turned on, it will start physically (all fans are rotating, disks start up...) but not give a ...
20
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3answers
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What is hyper-threading and how does it work?

I've heard the term hyper-threading thrown around a bit recently, what exactly is hyper-threading and why is it important?
18
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3answers
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Why does my Intel i7-920 display 8 cores instead of 4 cores?

When I go to the task manager I see 8 processors but I know that I have 4. Why?
17
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3answers
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Why is my laptop both dual core and quad core at the same time [duplicate]

I bought an Alienwaremx14 with the following specifications , it is clearly stated here that my CPU is dual core However when i open Window task manager , I was shocked to find out I had four CPU ...
17
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8answers
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CPU Temperature sensor wrong?

Everest Ultimate is suddenly telling me that the CPU temperature (and core temps) for my E6850 Core 2 Duo is 72 degrees Celsius. When I stress-test the machine, the temp goes up to 91 degrees and the ...
16
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10answers
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Why aren't all CPUs 'overclocked' as a factory default? [duplicate]

Possible Duplicate: Why are modern CPUs “underclocked”? When I was searching around for a desktop awhile back I came across a lot of discussions where techies talked about ...
16
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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?
16
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3answers
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Will Windows give me problems if I upgrade my processor?

Assuming the motherboard and BIOS will support it, can I change from a dual core processor to a quad core without Windows 7 giving me any grief?
16
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3answers
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What does the processor do when I copy things from one USB disk to another?

Is all data that I copy going through it or is there another more direct way?
16
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2answers
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Why are newer generations of processors faster at the same clock speed?

How come, for example, a 2.66 GHz dual-core i5 will be faster than a 2.66 GHz Core 2 Duo (also dual-core)? Is this because of newer instructions that can process information in less clock cycles? ...
16
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2answers
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When you start multiple threads on a multi core processor, are they guaranteed to be processed by different cores?

I have a Pentium core i5 processor, which has 4 cores. If I do this in a C# console program var t1 = new Thread(Thread1); var t2 = new Thread(Thread2); t1.Start(); t2.Start(); are t1 and t2 threads ...
16
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4answers
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Why is a single thread spread across CPU's?

I'm just curious why the scheduler constantly moves an app between CPUs, rather than keeping it on one. It looks a bit silly to have 4 cores at 25% rather than one at 100%. Does it has to do with ...
15
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3answers
2k views

Task Manager is saying the system is running with over a thousand threads

I opened up Task Manager and looked under the "System" area and saw: Threads: 1337 Since I have a dual-core processor with hyper-threading available (meaning four threads), how is it possible to ...
15
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5answers
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Why has the size of L1 cache not increased very much over the last 20 years?

The Intel i486 has 8 KB of L1 cache. The Intel Nehalem has 32 KB L1 instruction cache and 32 KB L1 data cache per core. The amount of L1 cache hasn't increased at nearly the rate the clockrate has ...
15
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2answers
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What are threads, and what do they do in the processor?

I was looking at the stats for the Intel Pentium e5700 CPU. It has two cores and two threads. What do the threads do for the processor? Is there any relation between the number of cores and the ...
15
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2answers
322 views

Are 64-bit processors “faster” than 32-bit ones, simply because they are 64-bits? [duplicate]

I have pondered that some say "32-bit is old news" because you are limited in RAM without cutting around, such as with PAE. Assuming first that the following factors weigh in on the processor's speed ...
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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 ...
14
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2answers
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Where are Intel Itanium chips used?

I think that all the Intel chips I've ever bought were IA-32 architecture. Are Intel Itaniums sold in desktops or laptops?
14
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2answers
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What is the difference between Pentium(number) and just Pentium?

I noticed some older CPUs are branded as Pentium(n) (Pentium followed by a number), but there's some relatively new computers on shelves that just say Pentium with no number. Are those processors ...
14
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2answers
2k views

Does the Intel i7 offer real improvement over its predecessors? [closed]

As the questions title asks, do the new processors from Intel offer real, as in noticeable, improvement over the previous quad core ones? What does the i7 actually offer that is new or is it simply a ...