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docseuss68

macrumors newbie
Original poster
Mar 1, 2008
10
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Just installed Vista 32 bit home premium on Mac Pro 2.8 dual-core with 4gb ram (2 Apple + 2 OWC). Wondering why only 2gb ram showing up? Thought 32 bit would recognize up to 4gb (including size of graphics card – here the 512mb geforce 8800). So seems like it should be showing around 3.5gb ram.
 
Nope, sorry Vista 32-bit is limited to 2GB. There are workarounds though, they have been posted before, but I can't remember where, also look on Arstechnica's forums.
 
Its an artificial limit so maybe MS is just being nice to business customers. There is no real reason for any limit at all AFAIK.

It's the limitation of having a 32-bit address space. All 32-bit OS's suffer from this. It's not an artificial limit, it's an architectural limitation. 64-bit processors and OS's were created to get around this limitation (as well as PAE, but that's more of a quick fix).
 
Switch to Vista 64. Its free, your 32bit serial is interchangeable with 64bit versions. You can either pay microsoft $10 in shipping and handling and get an official 64bit disc via their 64bit orderform or find "alternative" methods to get an iso of the 64bit disc and burn it to a DVD yourself (the version of windows doesnt matter, ultimate, basic, whatever, they are all the same dvd's. your serial determines which version to install).
 
It's the limitation of having a 32-bit address space. All 32-bit OS's suffer from this. It's not an artificial limit, it's an architectural limitation. 64-bit processors and OS's were created to get around this limitation (as well as PAE, but that's more of a quick fix).

PAE is included with the Pentium Pro and Athlon and above and allows up to 64GB RAM. I don't think Vista runs on any earlier systems anyway so there is no reason for Microsoft not to use it.

Switch to Vista 64. Its free, your 32bit serial is interchangeable with 64bit versions. You can either pay microsoft $10 in shipping and handling and get an official 64bit disc via their 64bit orderform or find "alternative" methods to get an iso of the 64bit disc and burn it to a DVD yourself (the version of windows doesnt matter, ultimate, basic, whatever, they are all the same dvd's. your serial determines which version to install).

Not if you have the OEM version of Vista. They don't include a free upgrade to 64 bit.
 
If your machines only sees 3.5GB when you have 4 installed you can add the /PAE switch to the boot.ini. This will increase it to 4GB. I know for a fact that this works on Windows 2003/2008 server, haven't tried it on Vista Business though.
 
If your machines only sees 3.5GB when you have 4 installed you can add the /PAE switch to the boot.ini. This will increase it to 4GB. I know for a fact that this works on Windows 2003/2008 server, haven't tried it on Vista Business though.

will this work on a q6600 prcessor?


as far as free 64bit os, does this apply to the msdn alliance for universities ( i got vista buis 32 bit for free)


would this also work on xp pro 32 bit?
 
Nope, sorry Vista 32-bit is limited to 2GB. There are workarounds though, they have been posted before, but I can't remember where, also look on Arstechnica's forums.

Funny.. My mom's computer shows 2.24 GBs, and my old pentium 4 shows 3.5 GB (vista home premium, ultimate)
 
Funny.. My mom's computer shows 2.24 GBs, and my old pentium 4 shows 3.5 GB (vista home premium, ultimate)

I've been proved wrong on this, but it still doesn't show more that 4GB with the limit being between 2GB and 4GB.
 
will this work on a q6600 prcessor?


as far as free 64bit os, does this apply to the msdn alliance for universities ( i got vista buis 32 bit for free)


would this also work on xp pro 32 bit?
Good question. Like I said - the server versions do support this but I haven't used 4GB with Vista/XP before to find out. I'll have my new MBP within a week so I'll know then :D

If you have a boxed product 32 bit version you can get the 64bit for free (plus postage etc.)
 
Not if you have the OEM version of Vista. They don't include a free upgrade to 64 bit.
OEM is confirmed by people to work. You just have to call in to get an activation code since online activation will fail.
 
PAE is included with the Pentium Pro and Athlon and above and allows up to 64GB RAM. I don't think Vista runs on any earlier systems anyway so there is no reason for Microsoft not to use it.

It should be included with Vista 32 bit. I read an article from MS a few days ago about it. If you have DEP enabled, PAE is enabled.


And if you have Vista through MSDN AA, then you also get the option of downloading the 64-bit version. The CD keys are interchangeable.
 
This has been discussed numerous times on the this site -

windows 32 bit will show 3 to 3.5 gigs of ram. Yes - it varies from computer to computer, thats the joy of Windows! Unreliable and ugly!

64 bit versions will show all of it.

I have a PC with XP 32 bit and XP 64 bit. 32 shows 3 gigs. 64 shows 4 gigs (what i actually have).

Apparently the new XP serivce pack 3 will show all of it, but i have yet to download and install.
 
This has been discussed numerous times on the this site -

windows 32 bit will show 3 to 3.5 gigs of ram. Yes - it varies from computer to computer, thats the joy of Windows! Unreliable and ugly!

64 bit versions will show all of it.

I have a PC with XP 32 bit and XP 64 bit. 32 shows 3 gigs. 64 shows 4 gigs (what i actually have).

Apparently the new XP serivce pack 3 will show all of it, but i have yet to download and install.

Aye, it will show but it doesn't use all of it. Showing it is one thing, and I guess that's enough for users giving false security that it's actually using all 4g.

That's the real question here now isn't it. Even if it does show it, does it even use all of it? From what I have seen (I have a windows machine with 4g) and I can get 4g to show, but not all of it is used. The usage is similar to OSX. Even though 4g is shown, not all of it is used by the OS.
 
That's the real question here now isn't it. Even if it does show it, does it even use all of it? From what I have seen (I have a windows machine with 4g) and I can get 4g to show, but not all of it is used. The usage is similar to OSX. Even though 4g is shown, not all of it is used by the OS.

YES - but that speaks to the whole issue of people paying for HUGE amounts of RAM in their new boxes just because its cheap. I would suggest everybody look at their "resource meter" (Performance Tab in XPs task manager) and whatever its called in OSX and check to see how much RAM you are actually using. I do high-end 3D rendering at work, and whether its XP/software/my lack of skill - or all three - i never see it hit more than 3 to 3.5 gigs of ram.

I still see no reason to have 8 gigs of RAM. OR maybe I just I wish I could figure out a way to use it all.
 
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