What is the difference of 32-bit OS 64-bit OS?

More memory is available. This means that the processor is (if capable) can access 2^64 memory cells? But why, for example, in Windows available 3.5 GB of RAM, if 2^32=4 294 967 296 cells, which gives 4096 MB of memory?
June 3rd 19 at 19:28
2 answers
June 3rd 19 at 19:30
1. The processor can access much more memory than 4GB in a x86.
2. If you have 3.5 GB, it is very similar to what memory rummaged between the processor and integrated graphics card (if you have a external video card, such a misunderstanding can be disabled in the BIOS).
3. The most unpleasant consequence of using the x86 OS is a limit on the amount of memory given to the individual application. In Windows it's only 2GB. Install at least 128GB of RAM, each application will receive no more than 2! But you can run 20 pieces at a time, and swap will not be!
4. And under x64 applications run a little faster.
3. Not application and process. The application can run multiple processes and to grab memory for each. For example, Photoshop used to do that when something (now those who really need it, long on x64).
4. Actually not the fact. Depends on what the application is doing. Archiver, for example - Yes, when the CPU enough data from twice as large pieces, the work goes faster... - chelsea13 commented on June 3rd 19 at 19:33
In point , you are right - gerard_Stamm commented on June 3rd 19 at 19:36
About 4... Sometimes faster, sometimes slower, and almost never... To simplify understanding, I wrote "a little faster" - gerard_Stamm commented on June 3rd 19 at 19:39
, why ever. 64-bit applications take up more memory, increasing the chances to get into the swap on a machine with a shortage of RAM. And this is not just "a little slower" ;) - chelsea13 commented on June 3rd 19 at 19:42
June 3rd 19 at 19:32
It's a marketing limitation for the desktop version of Windows. Server 32-bit Windows can address up to 32GB of RAM
Server 32-bit Windows can address up to 64 GB of RAM

How so? - chelsea13 commented on June 3rd 19 at 19:35
And what's the problem?
https://support.microsoft.com/en-au/help/265173/th... - gerard_Stamm commented on June 3rd 19 at 19:38
, https://ru.wikipedia.org/wiki/PAE - gerard_Stamm commented on June 3rd 19 at 19:41
and where does the processing mode to the bitness of the operating system?
PAE mode can be used in both 32bit and 64bit system. - chelsea13 commented on June 3rd 19 at 19:44
and when that "server 32-bit Windows can address up to 32GB of RAM" because on server versions of 32-bit Windows, PAE is still enabled. And on the desktop - no, no. And PAE in x64 not needed at all. For in x64 so 64-bit used at address (64-bit line address, in contrast to the 36-bit line in PAE mode). - Gunnar81 commented on June 3rd 19 at 19:47
Included PAE will not help you allocate more than 4 GB to a process in a 32-bit system.
In addition, in addition to enabling PAE, the desktop version will still need to patch, because the limit of available system memory is locked for marketing reasons. - Jeff28 commented on June 3rd 19 at 19:50
,
Enabled PAE will not help you allocate more than 4 GB to a process in a 32-bit system.
And I somewhere spoke back?.. - chaz commented on June 3rd 19 at 19:53
Read the question of default. There asking why windows sees 3.5 GB, if the processor can address up to 64g. I answered - because the limitation is artificial.
Why would you tell me about PAE do not know. Write default. - Jeff28 commented on June 3rd 19 at 19:56

Find more questions by tags Operating systemsProcessors