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Hello

My new system has 4GB of Ram and runs XP.

I have read alot about using the 3GB swich in XP to allow PSCS2 to access greater than the standard 2GB of ram.

Alot of people can't get it to work and it seems dangerous to try.

I have read conflicting reports on whether it works and what is the best way to do it safely.

Does anyone have any clear notes on this or has done it sucessfully (or otherwise) themselves.

Thanks

So far as I known, WINXP only supports, recognizes, reads maximum of 2Gb RAM.
If OS only supports 2Gb RAM, how application can handle 3 or 4Gb RAM.
Maybe someone may chip in.

XP64 perhaps?

What about on a Mac?

gstark wrote:XP64 perhaps?

What about on a Mac?

Yes, XP64 is the answer.

MAC? An Apple for the day?

MAC - it just works

MAC 16 gigs in the new quad G5

Spooky is asking about PC + WINXP/ Not MAC, also he's not MAC user, so please not go off topic.

relax..

Photoshop CS2 is a 32-bit application. When it runs on a 32-bit operating system, such as Windows 2000, Windows XP Professional, and Mac OS v10.2.8, it can access the first 2 GB of RAM on the computer.The operating system uses some of this RAM, so the Photoshop Memory Usage preference displays only a maximum of 1.6 or 1.7 GB of total available RAM. If you are running Windows XP Professional with Service Pack 2, you can set the 3 GB switch in the boot.ini file, which allows Photoshop to use up to 3 GB of RAM.

Here you go Spooky

http://www.adobe.com/support/techdocs/320005.html

This should help you.

shutterbug wrote:relax..

Photoshop CS2 is a 32-bit application. When it runs on a 32-bit operating system, such as Windows 2000, Windows XP Professional, and Mac OS v10.2.8, it can access the first 2 GB of RAM on the computer.The operating system uses some of this RAM, so the Photoshop Memory Usage preference displays only a maximum of 1.6 or 1.7 GB of total available RAM. If you are running Windows XP Professional with Service Pack 2, you can set the 3 GB switch in the boot.ini file, which allows Photoshop to use up to 3 GB of RAM.

But the WINXP is only seeing, recognizing only 2Gb RAM, how can its application access to unseen 2GB? Pls. clarify.

Please see link

Photoshop is a 32bit single threaded application it can't address more than 2GBs of ram, you will need a true 64-bit platform with 64 bit operatign system and 64-bit photoshop, like Photoshop 3.0 on IRIX on the Silicon Graphics platform

there are some filters on mac osx photoshop optimized for 64-bit processing liek guassian blur but the core application cannot address more than 2gig of ram

Gidday Spooky,

XP Home/ Pro support 4GB Memory
http://www.microsoft.com/windowsxp/pro/ ... tures.mspx

Here is a MS Memory Diagnostic software, don't know if that will help.
http://oca.microsoft.com/en/windiag.asp

There is plenty of google posts about the swiches. Also looks like something in SP2 for XP may limit the system to 3GB. Must be one of those "features" that MS like giving us.

Have a look at these Technet articles:
http://support.microsoft.com/kb/888855
http://support.microsoft.com/kb/291988
http://support.microsoft.com/kb/833721
http://support.microsoft.com/?id=888137

Unfortunatly I haven't got 4GB of RAM to play with other than on my Production Servers here in the office. Something about SLA's and uptime stop me from tampering with those too much.

Here is a google search:
http://groups.google.com/groups?q=XP+pr ... y&start=0&

Sorry I can't give you any personal experience.

Cheers

I can't be done with all PC and MS is not supporting this task wisely.

Important: The 3GB switch is a Microsoft switch and may not work with all computers. Contact Microsoft for instructions before you set the 3 GB switch, and for troubleshooting the switch. You can search on the Microsoft support page for 3gb for information on this switch

I want to try the /3GB switch but my biggest concern is if I try the /3GB switch in my boot.ini file which is suppose to enable PSCS2 to use 3GB and my PC reacts badly and won't boot then I am sort of stuck. I can't get into the boot.ini to remove the switch to fix it.

Any ideas?

If you have two logical volumes in your system, you can install a second WinXP setup just for this purpose. You can play to your heart's content, and just reboot to switch between versions.

We do that all the time here ...

Looks like I have done it sucessfully.

I followed the below advice and it worked. Photoshop now showing Available Ram 2655MB up from 1764MB before the switch.

Here is the idea I followed, found it on outback photography forum. You need to setup the two OS lines like he says because my system hung with the USERVA allocation on 3072. I had to back it off to 3018 before it worked.

____________________________________________________

I have been using the 3GB flag for a few months with no problems (after a few adjustments). Here is what you want in boot.ini:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microsoft Windows XP Professional 3GB" /fastdetect /3GB /USERVA=2944 /NoExecute=OptIn
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microsoft Windows XP Professional" /fastdetect /NoExecute=OptIn

> Note that there are 2 OS listings - the 3GB and also the standard (2GB) version. This allows you to reboot and choose the standard if you have problems. You can then adjust the settings for the 3GB version and try again.
> The USERVA (user virtual address) switch is used to adjust the amount of ram allocated to the user. I found that the default 3GB (3072) would not boot properly. I started adjusting down in 64MB increments until I found a setting that was stable. (64MB increments was an arbitrary choice on my part.)
> I set Photoshop to access 95% and it now shows 2443MB of ram dedicated to Photoshop. I can definately tell the difference.

I hope this helps - David Rayburn Haynes (drh@drhaynes.com)