RAM with 32 bit vista

I was wondering exactly how much ram vista 32 can actually use. I've heard 3.5GB from one person and only 3GB from another. can anyone bring truth to this?

 

Yes.

It really really depends on your computer configuration. I've seen numbers like 2.5GB, 3.0GB, 3.2GB, and 3.5GB between various computers.

 

32 bit Microsoft operating systems can typically use a maximum of 3.12GB. Although they can sometimes detect more if it is installed, the limitation of use remains in place.

source

 

3.5 for me on machine in sig.

 

However, the maximum memory available in 32-bit versions of Windows Vista is typically 3.12 GB.

emphasis mine.

 

Is there some inference in that statement that XP is somehow different?

AFAIK, XP/Pro will not use more than 2GB for applications and processes.

Source (XP)

 

so, anyone think I should get 4GB...just in case?

 

I would either go with 2GB or 4GB to keep the dual channel symmetry in place. Unless I had plans to go to a 64 bit OS in the near future, I would lean towards 2GB.

 

Go for 4GB (its cheap), and upgrade to 64bit.

 

It's a bit of a waste at this point, but if you get a REALLY good deal, then it might be worth it.

That extra RAM won't hurt your computer, it'll just sit there andl faithfully wait until you return with a 64-bit OS. It will never have an affiar with another computer or cheat on you. Quite unlike my ex.

 

The emphasis was on "typically".

 

You could try out the 4GB with 32-bit, and you might see somewhere around 3.75GB, same as this user....j/k (bug !!)

 

The 2GB limitation is not the same as the 3.12GB limitation. The total system memory is limited to 3GB+ in 32-bit operating systems because of the memory address requirements of other devices. Then in Windows, out of that 3GB+ total memory, half is reserved for the kernel and the other other is available for actual applications. So if a full 4GB were recognized, 2GB is for the kernel and applications themselves can only use 2GB. This is the design of all Windows OS (XP or Vista) since kernel and applications always share memory.

Mac OS X is designed differently. Applications and the kernel are swapped and get exclusive use of the full memory space when in use, which is why even in 10.3 Panther, applications can use the full 4GB (minus device addresses) even on 32-bit processors instead of being limited to 2GB.

There are tradeoffs of course, since constant swapping between the kernel and the application wastes bandwidth and takes time. However, OS X does keep a subset of the most commonly used functions of the kernel in memory all the time, but this takes a lot less room than the half the available memory that Window's kernel always takes up.

 

is it a bad idea to use a 1gb stick and a 2gb stick?

 

The mathematical limitation of 32 bit addressing is ((2**32) - 1) bytes.

 

I believe the link you posted is just giving 3.12 as an "example".

According to a Microsoft Software Test Engineer, it's from ~2.75GB to 3.5GB.

http://blogs.msdn.com/hiltonl/archive/2007/04/13/the-3gb-not-4gb-ram-problem.aspx

Yes, I've seen systems that can use 3.5 like maxpower47.

And for XP, I believe with SP3 you don't need to add the /3GB switch manually to enable PAE, cause I never added that switch and XP is automatically in PAE mode with 3 GB of RAM.