32 or 64 bit Windows 7 on Parallels?

Hi guys - anyone which would be a better performance route when using parallels 5 ?
i would probably using the same image for bootcamp and parallels... so any difference in performance in using the 32 bit or 64 bit version of windows?

thanks

 

32 bit would be best, because you can't allot 4GB(basically the min for 64 bit) in a Macbook with 4GB. If your laptop has more than 4GB, then yes, get 64 bit.

 

thanks....seems to make sense..yeah to start I will have a 4gb macbook....and probably allot around 2gb for windows

but then when i use the same image as my bootcamp...then i would have the full 4gb available?

 

Only if you use the 64bit version.

 

With bootcamp you get the full 4GB's(with 64 bit Windows, with 32 bit you get a little over 3GB). What macbook are you looking at?

 

4gb is not the min for 64-bit. I've been running 64-bit Windows with 2 gb for years. It's true that the biggest advantage materializes with 4 gb or more of RAM... but it runs just fine with less.

32-bit is slightly more RAM efficient, so if you want to run with less than 2 gb allotted to the VM, that might be better... 32-bit also uses a few less gb of disk space, and boots more quickly.

So, if this image were for a VM only, I'd suggest 32-bit, since as mentioned you can't allot all your RAM to a VM.

However, you (the OP) indicated that you may want to boot the image with bootcamp, i.e. not in a VM, so then using 64-bit will allow you to use your full 4 gb of RAM when doing that.

Also, if you ever upgrade beyond 4 gb (if your computer supports it), you'll then be able to use 4 gb or more in a VM too.

 

Sorry, I should have clarified. What a meant was 64 bit Windows is useless with less than 4GB's memory. I think the minimum for Windows 7 64 bit is 2GB's.

 

You just contradicted yourself!! Stop talking about things which you can only guess at!

 

I've tested Windows 7 32bit and 64 bit on 2GB system and it runs very well. There's many systems shipping with Windows 7 64bit running 2GB and they run fine. Of course if you use demanding apps then you could end up swamping more than necessary which will slow you down.

The main reason for going with the 64bit version is gaining access to more than 4GB for the OS and native apps.

 

No I didn't, the 2GB minimum is from Microsoft, the useful/logical minimum is 4GB's.

http://www.microsoft.com/windows/windows-7/get/system-requirements.aspx

I'm not guessing at anything, I've owned at least 80 laptops and desktops.

Yes, Windows 7 64 bit will run great on 2GB's, but unless you are planning on upgrading to 4GB or beyond, its useless.

 

the 13inch 2.4ghz with 4gb ram

 

So yes it runs great with 2GB and at the same time it's useless without 4GB?

 

i'd say 64 bit windows with 2gb of ram isn't useless when you want to run a 64 bit app

 

No difference.

 

some emulators and graphics programs have 64 bit optimizations.

64 bit windows with 2 GB of ram is not useless.

1. Useless is a more extreme word than you were prepared to use. perhaps you meant "has no additional benefits over 32 bit windows" (useless implies "no use")

2. Occasionally there are 64 bit optimizations (sometimes very significant) in programs that don't rely on having 4GB+ of memory. It just isn't that simple.

3. If you intend to upgrade to 4GB+ of ram in the future, it won't require reinstalling the operating system.

 

How can something "run great" and be "useless" at the same time??

 

64 bit Windows is really meant(useful) for 4GB's or more. It will run fine on 2GB's, but the whole idea of 64 bit is for 4GB's or more. Actually using 64 bit on 2GB's of memory lowers your performance. Because 64 bit when idle uses around 800MB's, while 32 bit uses around 500MB's.

 

What he said.

 

it still depends. the science behind the operating system is very complicated.

a 64 bit operating system handles data differently than a 32 bit operating system.

in windows, there are additional security features available only 64 bit operating systems. and, software written specifically to take advantage of 64 optimizations can have increased performance (unrelated to the amount of memory you have). 64 bit windows can handle more memory than 32 bit windows, but it only requires 1 GB, and will do well with 2 GB+. The limit for 32 bit windows is approximately 4 GB.

you always need to have enough memory to store data for the programs you are running. having more memory than that will not change performance. having less will cause massive drops in performance.

 

64-bit kernel OSX has been benchmarked between 5-10% faster than the 32-bit kernel under certain tasks, so I would imagine there are similar improvements in the two windows 7 versions.