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

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324
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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 ...
288
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15answers
125k views

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 ...
160
votes
15answers
28k 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 ...
137
votes
5answers
361k views

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 ...
136
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8answers
1.4m views

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?
108
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6answers
215k views

How can I monitor the CPU temperature under linux?

How do I monitor and display the CPU temperature using Linux?
100
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13answers
16k views

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 ...
87
votes
11answers
49k 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 4GB of ram and 2.3GHz quad-core and my iMac is even ...
78
votes
8answers
349k 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-> ...
65
votes
6answers
25k views

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...
62
votes
4answers
14k views

How can my computer use 300% PC processing power?

I'm playing around with a script and well I got carried away (it's still running right now and yet my computer has not yet died). I'm running 17 iterations of the script (with the intention of ...
58
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12answers
145k views

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 ...
57
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9answers
14k 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 ...
52
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14answers
16k views

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 ...
51
votes
5answers
7k views

Are CPU clock ticks strictly periodic?

Is the frequency of a CPU a mean value of about how many clock ticks there are in a second or does it have a more strong, physical stability? In my opinion, it must be not stable nor unstable. So ...
51
votes
7answers
38k 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 ...
50
votes
5answers
11k 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 ...
50
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5answers
10k views

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 ...
42
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6answers
18k 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 ...
42
votes
1answer
4k views

Meaning of Intel Processor suffixes

I just bought a Core i7 2nd generation machine which shows the processor in the BIOS as: Intel Core i7-2620M CPU @ 2.70Ghz I have seen i7 3rd and 4th generation processors on Google but I am not ...
40
votes
2answers
19k views

Is there a way to identify the busy (CPU-consuming) tab in Firefox? [duplicate]

Sometimes there's a nasty, guilty, CPU-hogging tab in Firefox that's maxing one of my CPU cores and making the whole browser sluggish. I'd like to find it and close it. Sometimes I get lucky, but ...
39
votes
8answers
81k views

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 ...
38
votes
4answers
119k views

How to reduce Google Chrome's CPU usage?

I have started using Google Chrome (up to date) on Windows 7 (everything up to date) on a clean install I did a few days ago and compared to Firefox I am seeing huge CPU spikes (up to 100% CPU ...
35
votes
4answers
3k views

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 ...
34
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2answers
106k views

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?
34
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3answers
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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 ...
33
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14answers
7k 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?
33
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5answers
8k 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. ...
32
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7answers
12k 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 ...
29
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9answers
5k 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, ...
29
votes
4answers
3k views

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 Hyper-...
28
votes
6answers
25k views

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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2answers
24k views

What is a PCI-Express Lane?

I am reading an article bemoaning i7-5820K Will Only Have 28 PCI-Express Lanes compared to its sibling processors having 40 lanes. Isn't 28 lanes already too many? How many lanes would a normal home ...
27
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4answers
12k 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 ...
27
votes
7answers
2k views

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 "...
27
votes
5answers
33k views

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 ...
27
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5answers
8k 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 ...
27
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3answers
13k views

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?
25
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3answers
2k views

Why are newer generations of processors faster at the same clock speed?

Why, for example, would a 2.66 GHz dual-core Core i5 be faster than a 2.66 GHz Core 2 Duo, which is also dual-core? Is this because of newer instructions that can process information in fewer clock ...
24
votes
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 ...
24
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7answers
98k views

TiWorker.exe - Very High CPU Usage

I have a laptop running Windows 8. Although it originally ran well, it started having very bad performance issues. I decided to perform some research into the topic. Opening up Task Manager, I ...
21
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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 ...
21
votes
8answers
66k views

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 ...
21
votes
2answers
73k views

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 ...
21
votes
1answer
44k views

What happens if I use RAM of a faster speed than the CPU supports?

Looking at the Intel E3-1230v2 CPU, under Memory types it says "DDR3-1333/1600". My question is, in what way does the CPU limit the RAM speed? What would happen if I put in a DDR3-2133 RAM chip ...
20
votes
5answers
71k views

How much memory can a 64bit machine address at a time?

If the memory is byte addressable, shouldn't it be 2^64 / (2^10 * 2^10 * 2^10) = 2^34 GB ? A general Google search says 8GB or 16GB max. How is that true? Also, how does it depend on the Operating ...
20
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3answers
2k views

Does a CPU heatsink need to cover the entire CPU package? (Xeon E5-1650, Arctic Freezer i11)

I've just purchased an Intel Xeon E5-1650-V3, which I intend to use in a workstation (mid-tower). As a CPU cooler, I bought an Arctic Freezer i11. (The motherboard is an ASrock X99 Extreme4.) I've ...
19
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10answers
3k views

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 taking ...
19
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6answers
26k views

Where exactly L1, L2 and L3 Caches located in computer?

Where exactly L1, L2 and L3 Caches Located in computer ? I know, we use Cache to increase performance by picking DATA and INSTRUCTIONS from Cache rather than Main Memory. Following are my questions ...
19
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6answers
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What is the safe temperature range for a Core-i5 processor?

I have an HP laptop with with a Core-i5 450m processor and an ATI Radeon 5650 1GB graphics card. When I played crysis warhead on my system its temprature went up to 82° c. Is it safe to play games up ...