You can install at least 4Gb of memory on most motherboards today, but apparently you shouldn't install more than 3Gb if you're not running a 64-bit operating system.Why?Can't a 32-bit version of Windows (or Linux, or whatever) address 4,294,967,296 bytes (two to the power of 32) of memory, by definition?When I open Task Manager and click the Performance tab, I see the memory limit is way more than 4Gb. I understand that includes the swap file, but if Windows can handle 8Gb or whatever of total memory including swap, why can't it handle 4Gb of physical RAM?Steve
The executive summary: Yes, a plain PC running a 32-bit operating system - and if you're wondering if that includes your PC, then it almost definitely does - shouldn't have more than 3Gb of RAM (as I mentioned in passing in this Ask Dan), if you don't want to waste quite a lot of the last gigabyte.
If you install 4Gb, there is no way to make all of the RAM between 3Gb and 4Gb available without installing a 64-bit OS, which you can't do unless you have a 64-bit CPU. And even then it won't necessarily work.
So, to avoid hassles on current systems, it's best to stick with 3Gb or less.