Possible Duplicates:
Why does Windows only show about 3.5GB of my 4GB+ of RAM?
Why can't Windows 7 x64 use all installed memory?
On Acer 1830t notebook with 4GB RAM (Intel HM55 Express + Intel GMA HD) and custom Windows 7 install Intel® HD Graphics utility reports
Physical Memory: 2869 MB
Minimum Graphics Memory: 128 MB
Maximum Graphics Memory: 1306 MB
There's no BIOS setting to disable shared video memory.
How do I bring RAM back to 4GB?