Computer architecture refers to various aspects of computer system designs which can affect compatibility, performance, and interfacing. Some issues related to computer architecture can be processor word size, memory bus size, or protocol implementation.

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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 ...
151
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19answers
27k views

32-bit vs. 64-bit systems

What are the differences between 32-bit and 64-bit systems? If you have used both of them, what kind of sharp differences have you experienced? Would it be a problem to use 32-bit programs on ...
77
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18answers
19k views

Can some software physically damage hardware?

I know a question similar to this one has been asked before however it was about installing a 32bit OS on a 64bit laptop. My question is more about damaging the hardware. I was wondering if there was ...
57
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6answers
13k 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...
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9answers
9k 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 ...
46
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16answers
4k views

Why do computers count from zero?

Computers traditionally tally numerical values starting from zero. For example, arrays in C-based programming languages start from index zero. What historical reasons exist for this, and what ...
31
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5answers
2k views

How can computers calculate exponential math without overflow errors?

Studying some RSA encrypt/decrypt methods, I found this article: An Example of the RSA Algorithm It requires this to decrpyt this message The total result of is so big, for a 64-bit/32-bit ...
31
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5answers
5k 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. ...
28
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9answers
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How can I enable PAE on Windows 7 (32-bit) to support more than 3.5 GB of RAM?

I know that Windows XP 32-bit can be configured, through PAE, to support more than 3.5 GB of RAM. Is there a good tutorial to do this with Windows 7 32-bit? As to why I don't simply use 64-bit ...
24
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3answers
25k views

How to check my RAM configuration (Windows 7)?

I would like to check my RAM configuration. I know it is easy to check the total RAM installed on a computer (eg 32 GB), but is there an easy way to check in Windows if the RAM is e.g. 2x16 GB, 4x8 ...
19
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7answers
26k views

What is the maximum amount of ram a 64bit machine can theoretically address?

I'm reading through my computer architecture book and I see that in an x86, 32bit CPU, the program counter is 32 bit. So, the number of bytes it can address is 2^32 bytes, or 4GB. So it makes sense ...
14
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5answers
16k views

Is a higher core count or higher clock speed more beneficial to a computer's performance? [closed]

With lowering silicon costs and rising consumer needs, manufacturers seem to be pushing one of two things: clock speed and/or core count. With the way things are going, it doesn't seem that clock ...
13
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10answers
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How can I determine if the current version of Windows is either 32-bit or 64-bit from the command line? [duplicate]

What's the command line to find out if the OS is running a 32-bit version or 64-bit of Windows?
13
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6answers
7k views

What are “Instructions per Cycle”?

I've been learning a little bit more about how processors work, but I haven't been able to find a straight answer about instructions per cycle. For instance, I was under the impression that a four ...
13
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3answers
8k views

Why are there so many pins on a sata power connector?

I was just looking at the power connector for a SATA optical drive, and noticed that it had fifteen pins! I then marveled at the data connector next to it, which has a measly seven pins. I know that ...
12
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5answers
4k views

Why multi core processors?

Why are chips containing more and more cores? Why not manufacture a larger single-core processor? Is it easier to manufacture? Is it to allow programs to multithread using seperate cores?
11
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7answers
14k 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 ...
11
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3answers
642 views

Will a new processor with slower clockspeed run legacy applications faster?

I'm using Linux and have an old P4 with about 3 GHz clock speed. Will a newer chip that had slower clock speed run my legacy applications faster or slower? I only use one application at a time, an ...
10
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2answers
5k views

Why does RAM need to be installed in pairs?

Why does RAM need to be installed in pairs? What's the reason behind this?
10
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2answers
410 views

On x86 architecture, why are there fewer bits for virtual address space than physical?

I was reading this article on 64 bit computing, and it mentions: For example, the AMD64 architecture as of 2011 allowed 52 bits for physical memory and 48 bits for virtual memory I would think ...
10
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3answers
1k views

How does xeon differ from regular processors?

Yes I know that Xeons are meant for server use, require different motherboards and you can have more than one of them in a box. But technically how is a Xeon processor itself different from a regular ...
9
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7answers
17k views

How to find the architecture of OS installed?

I'm using Core 2 Duo. So, from Intel website I found that it is 64-bit architecture CPU. Long back I've installed Ubuntu OS on this machine. But I'm not sure if I installed x86-32 or x86-64 version ...
9
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2answers
6k views

How do I interpret the specification of memory (RAM)?

When looking at memory there are a few specifications that I don't understand and was hoping to have clarification on. What do these terms mean, and how do they affect the systems performance? Feel ...
7
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2answers
384 views

Alternatives to the 0 and 1 bit style/structure

I've looked everywhere for this answer or even at least a question like this one (even tom's hardware didn't have anything 'explicitly' related to this). My question is simple: Is there or are there ...
7
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2answers
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How does the CPU write infomation to ram?

My question is, how does the CPU write data to ram? From what I understand, modern CPU's use different levels of cache to speed up ram access. The RAM gets a command for information and then sends a ...
6
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9answers
33k views

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.
6
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2answers
326 views

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?
6
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3answers
402 views

If the size of the (accessible) RAM is limited, why isn't the hard disk?

When the number of possible RAM adresses is limited by the computer architecture (32/64 bit), why isn't the size of the hard disk limited? Or is it limited? If yes, what would be the highest possible ...
6
votes
2answers
111 views

Run 10 sets of headphones from a pc via 10 separate channels

We have a PC application that runs on Windows 7 platform that is designed to play sound to up to 10 different MP3's to up to 10 separate sound cards (ie. 10 different inputs playing to 10 different ...
5
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5answers
715 views

Why are GPUs cheaper than CPUs?

What are the technological reasons whereby GPUs are cheaper than CPUs?
5
votes
4answers
618 views

Why can't memory clock speeds be as fast as the CPU speed?

I was reading that in old i386 based systems, the ram bus used to be the same speed as the CPU but when CPU frequencies increased, it became too hard to make RAM the same speed. Why can't we have 2GHz ...
5
votes
2answers
3k views

Calculating hard disk block model reading time

My professor posted a slide on how to calculate the data retrieval from hard disk using the block model. The specs were: 7200 RPM 5ms SEEK 80MB/s TRANSFER RATE BLOCK MODEL : Block size 4KB I ...
5
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4answers
1k views

How does increasing the number of transistors in a chip increase its speed

Is the only purpose of transistors in a cpu to act as the switches that define its instruction set? And if so then why does increasing the number of transistors increase its speed?
5
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2answers
176 views

32-bit to 64-bit skipping 48-bit?

Computer architecture upgraded from 16-bit to 32-bit to 64-bit. What was the logic for skipping 48-bit? What reasoning was used to upgrade to 64-bit and not some other exponent? The following tables ...
5
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3answers
5k views

What do the terms “asynchronous” and “synchronous” mean, with respect to the definition of an interrupt?

Quoted from http://en.wikipedia.org/wiki/Interrupt: an interrupt is an asynchronous signal indicating the need for attention or a synchronous event in software indicating the need for a change ...
5
votes
2answers
125 views

When powering off a computer, what exactly happens?

What exactly goes on when my computer is shut down? Not the "Shut down" button in the Start menu, but instead how the command (maybe machine code or something similar) is issued on a lower-than-OS ...
5
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1answer
482 views

Intel's AES-NI performance: Isn't the hard drive the bottleneck?

Will I see a performance gain with AES-NI using dm-crypt/LUKS for hard drive system encryption? Isn't the hard drive the bottleneck even without hardware acceleration?
5
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2answers
374 views

What type(s) of performance improvements to expect between architectures using QPI versus a FSB?

While comparing Intel's two new i7 processors, I noticed that the only difference between them apart from the L3 cache size and CPU speed is that one has QuickPath Interconnect, and that seems to ...
5
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0answers
196 views

Doing some detective work on old computer hardware [closed]

On a recent holiday to Bangkok, I visited the science museum and planetarium that is there. While eating lunch I was very surprised to see some very recognisable vintage computer equipment in almost ...
4
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6answers
6k views

Difference between cache memory and register?

What is the difference between cache memory and registers?I know them by definition but why do we need the other when we have any one of them?
4
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2answers
170 views

why are RAM chips independent of whether my system is a 32bit system or 64 bit system?

I was recently out to buy a 4 GB RAM chip for my laptop, and all they asked me was whether I wanted DDR-3? When I specified that I had a 64 bit system, they said that it's not important, my question ...
4
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4answers
3k views

How can I find a list of all SSE instructions? What happens if a CPU doesn't support SSE?

So I've been reading about how processors work. Now I'm on the instructions (SSE, SSE2, etc) stuff. (Which is pretty interesting). I have lot of questions (I've been reading this stuff on Wikipedia): ...
4
votes
4answers
4k views

Understanding “Flat memory model” and “Segmented memory model”

I am trying to understand Flat memory model and Segmented memory model. Are Flat memory model and Segmented memory model determined by CPU architecture or OS or both? Or are they not determined by ...
4
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2answers
724 views

Atomic operation. How does it guarantee consistency from hardware perspective?

Atomic operation. How does it guarantee consistency from hardware perspective ? How is it implemented in HW ? As far as I know, atomic instruction makes sure that when it is executed, no other ...
4
votes
2answers
94 views

Do someone know how to use this 8 GB space in ny computer?

I have same thing from a long time. I want to extend this 8.31 GB to c or d any drive. I tried but I got a error. see reference image. Do someone know how to do this in windows.
4
votes
3answers
352 views

What hardware is at physical address 0x80000000 on powerpc New World Macintosh?

Open Firmware device tree gives no clue what device might decode at physical address 0x80000000 to 0x8008200 on a G4 New World Macintosh. The mmu has three adjacent Virtual=Real translations for that ...
4
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1answer
953 views

Whats the difference between physical and virtual cache?

I am having trouble understanding what virtual cache actually is. I understand virtual memory. If the CPU wants to access memory, as far as I understand, it sends a virtual address to the MMU which, ...
4
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1answer
203 views

Why can't PCIe devices share lanes?

On older chip-sets it was not possible to have a dedicated graphics card in the PEG slot and have the Integrated Graphics Device (IGD) enabled at the same time. After looking online I found this was ...
4
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2answers
2k views

Is the size of a memory address and size of the address bus related?

My questions are about the relation between the size of an actual/physical address and the size of the address bus. If I understand correctly, the actual/physical address size is determined during ...
4
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3answers
313 views

How mouse button re-mappings work?

I installed my new mouse (Anker 2000 DPI Wireless) and then the driver which installs a program named '5-button mouse' that allows me to remap what each button does, standard stuff and everything ...