I have 8GB of ram on my server(Windows Server 2008 Standard, only Apache, PHP and MySQL Installed) however Task Manager says my Physical memory is only 254MB and this is not acceptable for a web server.
I think the problem is with a bios setting called "OS Install Mode" or something alog those lines.. It's still in there from some older OS's freaking out of the server has most then 256 MB of ram..
You might have thought it was something you needed to do when you installed the OS.. it's very misleading Check that. I think it will fix the problem.
Is the RAM (or other component) faulty?
I saw things like this while in the process of discovering that the new RAM was faulty: 12GB fitted but only ~8GB recognised (not being an exact multiple of 2GB was a major clue).