6g ram but only 3g recognized
 

I have set up a new Gateway DX4820 with Windows 7 to dual boot in Ubuntu 10.04

Windows shows it as having a Core 2 Quad Q8300 at 2.5 Ghz which meets the store specs but the system monitor in Ubuntu shows it as having 2.9 Ghz of ram.

No idea where to go with this. Any suggestions?

You need to install the 64bit version of Ubuntu.

with a 32 bit linux on a 64 bit computer you will only get aprox. 3.3 to 3.7 gig of ram
if you install the PAE kernel you can get 4 gig ( 4 gig - 1 bit)

I would install a 64 bit Linux OS

With such a new and fully VM supported machine, you can also consider virtual machines.

If you install the PAE kernel you can use almost all of your 6GB of ram (if you really have that), the same amount you could use with 64 bit Linux.

I would install 64 bit Linux, but that is my own behavior as distinct from my advice.

It is easy to switch to a PAE kernel in an existing 32 bit Linux. It is harder to reinstall the whole Linux system for 64 bit. Without knowing details of how kwalker will be using Ubuntu, I can't give any rational justification for (or against) the extra effort of switching to 64 bit Ubuntu.