Laptop not seeing memory

Hello; Need some help here. Have an ASUS netbook with Atom 330 processor and 2GB of ram installed. System says only 767MB available. Replaced memory with 2 - 2GB sticks from Crucial (limit on machine is 4GB). Rebooted and system still says 2GB installed and 767MB available. Any ideas?

Here is some info. The integrated GPU will use "X" amount of RAM (whatever your GPU is).
http://www.sevenforums.com/performance-maintenance/69189-asus-eeepc-netbook-memory-question.html
http://www.gilfether.com/problem-bo...05pe-netbook-with-the-black-screen-issue/214/

Thanks for the info. Still struggling. tried system config, selective start up; but use original boot config not accessible. Under boot advanced options max memory is not checked. Tried checking it and rebooting; came back unchecked. Computer is running very slowly.