Difference between 64 & 32bit

akhileshgrover

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Dec 28, 2011
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What is the difference between a 64 bit Operating system and 31 bit operating system?

How does it help a common user like me who uses the PC for basic net surfing and downloading movies?
 
64bit executes code in blocks of 64 bit 01111001100011000111000110010101010111000011000011010101010111000101

32 bit executes code in blocks of 32 bit
01100011001111100001111000111001

Theoretically if your code was always 64bit long numbers it could be twice as fast. But in reality most code can benefit 10-20% from 32bit versus 64 bit code.

64bit code also makes for bigger exe files and more memory usage. Becuse even if a number is not 64bit big it still consumes 64bit memory.

And offcourse it allows addressing of more RAM than 4GB (in reality because of OS 2GB pr. app.) because 2^32 gives a 4GB number.

And 2^64 gives a ridiculously much larger number 😉.

Im by no means an expert but I hope I made a bit sense and not completely blaah 😉
 

The same software will not run faster or slower on the same CPU and RAM PC.

And if it will, the user have running something else in the back ground.

x64 should be faster, but u can hardly tell the difference.
 
x64 is actually slower then x32 bit because of some background code and overhead but you won't notice the difference. It is only a percent or 3. You also can use higher amounts of ram depending on the OS version you purchase and the limits Microsoft puts on their versions.
 
Long story short, a 32-bit OS can only read 32-bits of data at one time. As a result, there is a hard limit of 4GB the system as a whole can access. [The amount usuable by you is less then that; usually around 3.25GB or so after hardware gets mapped. The amount usuable by a single program is only 2GB].

A 64-bit OS can use significantly more RAM, though the OS usually limits the total amount to something easier to manage [192GB for Win7 professional]. Another major change is that even 32-bit programs can access up to 4GB of RAM themselves, double what they could under a 32-bit OS [assuming they are compiled as LAA at least...]. So a memory intensive 32-bit application could see a significant speedup under Win64, though this is a rare case.

There are plenty of other under the hood changes, but to you, the increased RAM is the primary reason to go with a 64-bit OS. There is very, very little reason to bother with Windows 32-bit at this point.