(After reading this, you may also want to read the update that I posted.)
This morning I added extra 2GB of RAM to bring the total memory to 4GB total. I made sure that I purchased the same type of memory as the originals, Corsair TWIN2X2048 from NewEgg.com. NewEgg is a great place to buy stuff, they really care about their customers. I have a story to prove it.
After installing the memory I did a Google search on whther further steps were necessary. The properties of my computer showed the total memory as 3.25GB, but I wanted to make sure. Good thing I did. There is a file in the root directory of the boot drive, typically drive C:, called boot.ini. It instructs Windows XP on special steps of features to enable during the boot time. There appears to be two relevant soft switces that may need to be added, they are /PAE and /3GB. They are simply added to the end of a line in the boot.ine file. So, my boot.ini line looked like the following, your boot.ini file may be different:
Windows XP Professional” /fastdetect /NoExecute=OptIn /PAE /3GB
The parts in red are what I added based on my readings on Microsoft and other Web sites. There does not seem to be one correct answer that fits all, so I added these switches in different combinations and checked how much RAM the system reported when I went to the properties of My Computer, and how much RAM Photoshop reported. The amount of RAM reported by the system remained at 3.25GB with each combination, /PAE alone, /3GB alone, both present. Oh, if you add both switches /PAE needs to come first, as I read on one of the sites.
When I checked the amount of memory Photoshop reported, there was a definite change. The table below shows the reported RAM by the system and by Photoshop.
| Switch used | Reported RAM by | ||
| PAE | 3GB | System | Photoshop |
| 3.25GB | 1.693GB | ||
| X | 3.25GB | 1.693GB | |
| X | X | 3.25GB | 2.631GB |
| X | 3.25GB | 2.631GB | |
In the end, I left the line as shown above with /PAE and /3GB switches on.
There is another matter, the setting in the BIOS. I built my computer using an ASUS P5K WS motherboard and an Intel QX6700 CPU. One of the settings in the BIOS is called “Memory Remapping” and it can be enabled or disabled. Based on what I had read on various Web sites, I tried that feature turned on or off with no effect on the available memory. So, I left it the way it was and it is now enabled.
The addition of memory made a noticeable difference, not only in Photoshop but all the programs seem to load faster. I can comfortably run Lightroom 2.0 and Photoshop CS3 both of which start up rather rapidly. I bought the memory for $80 with a $30 rebate. I think this will be $50 well spent.
Related posts:
Looks like this is the limitation of a 32-bit operating system, with .75GB apparently spent on other hardware.
My current desktop supposedly can handle 8GB, so I loaded 6GB but seeing only 3.25GB. Then I learned that it needs to be loaded with Vista 64-bit to utilize the full 6GB of RAM. It is running Vista 32-bit now. I am not worroed as the speed is satisfactory enough.
Mary
I’m very pleased I found this encouraging article while designing my new PC for photo editing. Now I can tell that this 3GB switch works also on XP Home which I opted after some consideration having had a forum discussion at DPReview.com about XP Home vs XP Professional.
You use XP Professional and Adobe’s TechNote article “Optimize performance of Photoshop CS3 on Windows XP and Vista” states XP Pro having this 3GB option. So I took a risk by opting for XP Home as a result of my forum discussion.
In order to see how this switch would affect CS3’s performance I downloaded and installed Retouch Artists’ Photoshop Speed Test package and made the requested changes in Performance preferencies. Here are my test results:
XP Home booted normally, CS3 using 1271MB RAM (=75% of available 1695MB): test action lasted 64 seconds. CS3 using all available RAM: 42 seconds.
XP Home booted w/ 3GB switch, CS3 using 1695MB RAM (=now 64% of available 2633MB): test action lasted 30 seconds, 12 seconds less. Increasing the RAM to 2000MB and max 2633MB didn’t shorten the duration.
I did these test a couple of times and did exit and restart CS3 after the changes.