Start with the many articles about this like http://www.dansdata.com/askdan00015.htm
If something is unclear let's cover that and never again why 32 bit reports 2.5 to 3 point something RAM?
As to the hard disk, it may have been formatted in some other OS. Tell more.
I finished building a PC recently and when I loaded up BIOS, it detected all 4GB of Ram and both 1TB SATA harddrives. I installed Windows Vista 32-Bit (because 64-bit kept failing to install) and in System, it says I only have 2.5GB of Ram. It's not the sticks because we've tested it on another system. It also only shows my C-drive in Computer, with my second hard drive not showing up, however, when I go to hardware, both hard drives show up and are said to be working well.
Is there anyway I can make my second hard drive show up and utilise all my ram?
Any help with this would be greatly appreciated.