Photoshop CS3 memory limits in Windows

I'm running Windows Server 2008 Enterprise, and I have 8 gigs of RAM installed on this machine. It's a 32-bit version, but with PAE enabled it can see up to 64GB. Windows can see all 8 gigs.

In photoshop when I check under the performance tab and how much memory to allocate to the application it only says 1,678MB is available at 100%.

Is their something I need to do in order for photoshop to take advantage of my physical memory, or will it still use the memory even though its not specifically allocated to the application?

Any thoughts are appreciated.
Thanks, Kevin

According to this link from Adobe titled 'Optimizing CS3 with Windows XP/Vista', "Photoshop CS3 is a 32-bit application. When it runs on a 32-bit operating system, such as Windows XP Professional and some versions of Windows Vista, 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."

There's more info. that follows regarding running CS3 with a 64 bit processor, but I'm not sure that it applies to your current situation.

Thanks John,

I will have to read through that article a bit closer where it talks about CS3 on machines with more than 4 gigs of RAM. It sounds like it can still benefit from the additional RAM since the application shouldn't be using the pagefile as much.

PS can access up to 3GB of RAM in total. To get the extra 1GB (over the standard 2), you need to turn on the 3gig switch in the boot.ini menu. I believe it only works with XP Pro; however, and not XP Home. No idea if it will work with a server version. I've got it turned on and PS does have access to the additional RAM.

I've looked into PAE a little bit before, but haven't seen a good analysis of the benefits. Since it's an OS function that maps application memory addresses, it seems to me like the individual programs will still hit the 32-bit memory limit. But this may give PS 4 GB to work with, if it can use 4 GB that the OS isn't using. I'd be curious to know if you can get PS to see 4 GB, or anything close to it. Personally, I'd just rather run a 64-bit operating system and not worry about PAE.

Is anyone running CS 2 on Vista64? It seems to run fine on Vista32. I'm building a new system and will be loading Vista64 on it and can't afford to upgrade to CS4 at this time.

I'm running CS3 on XP Pro 64 (not Vista), and it can see approx 3.25GB, of 6GB installed. The 3.25 limit is because CS3 is a 32-bit app, as far as I can tell. I would expect the same or similar with CS2 on Vista 64, assuming you have 4GB loaded.

I now have a copy of CS4, which I will load at the weekend. I am expecting CS4 to see the whole 6GB.

Check into the 3GB switch on Windows Server first. The 3GB switch did not work correctly on my Windows XP Media Center OS and I had to go back to the normal config.