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I recently reinstalled my notebook, and my friend laughed at me because I didn't install the 64bit-version of vista instead of the 32bit one.

After which I wondered whether there was a great difference in performance with the 64 OS.

(I've always been sceptical about the 64bit version, because people used to tell me there were a lot of applications which didn't work anymore since they installed the 64bit version.)

So who can clear this up for me? :)

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migrated from Dec 23 '09 at 16:47

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You need friends with a better sense of humour. – skaffman Dec 23 '09 at 16:45
please mind your language. thank you! – Molly7244 Dec 23 '09 at 16:51

if you don't have to address memory beyond the 4 GB threshold, you're perfectly fine with a 32-bit OS.

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that is the case :) So I guess I didn't really make the wrong decision of choosing 32bit! – user22465 Dec 23 '09 at 17:10

Unless you're doing computational intensive tasks then you won't notice a difference between the 32-bit and 64-bit versions of your OS. I am running Windows 7 Home Premium 64-bit and haven't had a problem yet in terms of getting something to run. Windows does a great job at running 32-bit software.

Several years ago when Windows XP 64-bit came out there were lots of problems with software/drivers not running properly. However, much progress has been made since then.

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From a pure performance perspective, the answer will rely on the apps you're running. The 64-bit instructions are more efficient, but the memory pointers are larger, meaning less code will fit in cache. On average, the two effects cancel each other out, but there are cases where one or the other will dominate.

Since more people are still running 32-bit, the drivers for 32-bit will be easier to find and more thoroughly debugged.

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32-bit OS'es, in addition to not being able to use efficiently more than 4GiB of RAM, also can not efficiently mmap() files larger than 4GiB. This last part comes up more often than you'd think.

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Does anybody really needs to mmap >4GB at once? Any large file can be mapped by parts in 32-bit programme with mmap64(3) system call. So it is really no needs of expanding all your pointers TWICE for mmaping extra big files. OS can be 64-bit while running a lot of 32-bit programmes. – osgx Feb 6 '10 at 17:05

Your friend is a poor techie. Unless you have more than 3GB of RAM, there's no reason to use 64bit, and your processor will handle 32bit just as well - there's no rule saying 32bit processors are better at 32bit tasks.

If you have more than 4GB of RAM, you should definitely be on 64bit, however, as a 32bit OS will only give you ~3.5gb to play around with out of that. Else, feel free to laugh right back as he faces slightly increased RAM usage from having 64bit pointers* instead of 32bit pointers, with no upside! (unless he has more than 4GB himself)

*A tiny increase, to be sure, but it's potentially DOUBLE the ram usage! In actuality it's barely perceptible, but he's not dealing in fact either :P

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I'm still wondering about this one: I DO have 4GB RAM and you say the 32bit versions only use up to 3.5 GB's ... So that means I don't use half a gig of my memory, right? (But I also think it's not worth it to reinstall my whole system a 2nd time for half a gig extra) – user22465 Dec 23 '09 at 17:16
Well, depending on what other hardware you have installed, pretty much. A 32bit OS can only address 4GB of memory, and this includes your RAM, your graphics card's GRAM, your soundcard's memory, and so on. It's not worth reformatting over, but it's worth keeping in mind. – Phoshi Dec 23 '09 at 17:50

For a notebook, which has likely less than 4 GB of memory, 64 bit Windows would be overkill. The smart move is to run 32 bit Windows, which also makes it more likely that all drivers work and that most software runs.

Specifically, on e a notebook, you might actually prefer 32 bit Windows' ability to run DOS games.

And yes, 32 bit Windows would actually be faster than 64 bit Windows on most notebook hardware.

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As long as you have driver support I would have suggested 64 bit windows as well. You can try it and see if your apps perform any differently. Generally it's been my experience that the 64 bit windows multitasks alot better. I migrated a friend of mine who is a big gamer from 32 to 64 bit and he was able to go from haveing 2 WOW clients open (with framerate issues) to 4 with no issues. Others have changed at my office have had no real difference in performance running office apps.

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