On 22/07/10 22:33, ken wrote: > Is the 737M cached (in the output above) what is reserved for bios or > chipset...? and what is gained back through remapping? Nope, it simply means even if I had 2GB RAM, there'd be plenty I'm not using for anything but cache - I don't do much on this laptop but browsing these days :) What we are suffering from is explained neatly here: http://en.wikipedia.org/wiki/PCI_hole Simply put, if the BIOS+chipset does not support mapping these reserved areas to higher addresses this memory is lost to us. My Dell Inspiron 9400 is about 3+ years old now. More recent hardware have the necessary bits and pieces so that you can see all 4GB and use it with 64 bit or 32 bit + PAE. Server chipsets had this kind of support even earlier. Unfortunately for mine, Dell decided to only support 3GB.