Question : Problem: 3327MB Memory Cap & Reserved Space

We're running WinServer 2003 Enterprise on an IBM eServer xSeries 306 8836-1SU.  Originally configured with 512MB RAM, we recently upgraded to 4GB - the maximum capacity.

Upon boot, 4096MB is recognized as being installed; however, POST only tests 3327MB successfully.  From research, we understand that this is due to the memory allocation limitations in a 32-bit system, where anything above this tested range is reserved.

The question: is there any real net benefit, in this scenario, to maintaining 4GB of RAM, or is it more economical to scale back to 3GB, given that the last 1GB only yields an additional 256MB of usable RAM?  In other words, by having 4GB installed, do we truly "lose" the ability to utilize this RAM or is it used by those devices that have reserved the memory space in the first place?  Please feel free to elaborate in your response :)

Answer : Problem: 3327MB Memory Cap & Reserved Space

If the OS can't see all 4Gb then there is no point using the /PAE option.
Have a look in the BIOS, I know the intel boards I use allow me to use memory about 3.5Gb to allocate to the "system bus" for addressing.