Found this the other day when I was trying to figure out if my T61 laptop could be upgraded to more than 4GB of RAM (it physically doesn't support any more than that b/c the chipset can address more than that AFAIK):
http://support.microsoft.com/kb/929605 It also explains why you don't get the full 4GB, something which people here have already mentioned... BINO -----Original Message----- From: hardware-boun...@hardwaregroup.com [mailto:hardware-boun...@hardwaregroup.com] On Behalf Of Soren Sent: Saturday, September 19, 2009 8:06 PM To: hardware@hardwaregroup.com Subject: Re: [H] More than 4GB of ram and VM question Hey Brian, As far as I know, the Windows NT generation is not limited to 3GB RAM, only to 64GB (32bit O/S limit - do your own math ;). One thing is what the O/S reports (and what MS wants us to believe), and another thing is what's actually doable. Nothing new there, unfortunately. MS have several web pages describing the subject, though in very cloudy terms. The essence is that WIN only reports up to 'about' +3GB RAM, the rest is allocated to system (as in e.g. swap) and programmes. The often overlooked fact is that WIN will only allocate up to 3GB of RAM - per process, that is. How many processes are running on your system? I have build and/or setup several WIN NT systems with 4/8GB of RAM w/o any problems at all. Those are all A/V systems with RAID and all the bells and whistles, and no complaints so far. Oldest system is almost eight years old. It's kind of like the old NT-Switch-trick - only a few (like 2) keys in the registry are changed, and then you've got Server. Bummer. The limit for WIN NT Pro is 64GB by design (NT5/6/7/8=maybe). Home Edition is limited to 32GB, for whatever reason. Probably "bragging rights" :) It's all on the MS web site, though in very cloudy terms. But the determined individual will find it. Using +4 GB will include the "/PAE" switch in boot ini. Normally, this is added automatically by the O/S, and will run smoothly by so. For an A/V system for professional use, 32GB RAM is not unusual on e.g. WIN XP Pro. HTH >> -----Original Message----- >> From: hardware-boun...@hardwaregroup.com [mailto:hardware- >> boun...@hardwaregroup.com] On Behalf Of Brian Weeden >> Sent: Friday, September 18, 2009 5:29 AM >> To: hwg >> Subject: [H] More than 4GB of ram and VM question >> >> I'm currently running the beta on Windows 7 32-bit and using 2 sticks >> of 2GB >> RAM. I have a recent need to occasionally run a VM with another OS in >> it. >> I would like to assign that OS 2 GB of RAM, but as I only have 3.6 GB >> available and need to run some rather memory intensive apps in the >> native >> Windows OS at the same time, I can't. >> >> I'm looking at adding another 4 GB of RAM. I realize that a 32-bit OS >> can't >> address more than 4 GB, but my question is whether I can assign the VM >> to >> the other 4 GB? Or is that not going to work because it's running >> inside >> the host OS which has the limitation? >> >> And yes, I will probably make the move to 64-bit when Windows 7 >> actually >> comes out. >> >> --------------------------- >> Brian Weeden >> Technical Advisor >> Secure World Foundation <http://www.secureworldfoundation.org> >> Montreal Office >> +1 (514) 466-2756 Canada >> +1 (202) 683-8534 US > > >
