installed memory 4gb usable 2gb in windows 7 64bit

[Budhi Setiawan]

need help please
installed memory 4gb usable 2gb in windows 7 64bit
my komputer spec
CPU i5 750
mobo gigabyte p55-ud3l
his radeon 5670 128bit 1 gb
os win 7 64 bit
memory corsair vengeance 2x2gb

 

[kenrivers]

Look under things to try here: http://support.microsoft.com/kb/978610
The first thing mentioned is:
Check the system configuration settings
This problem may occur because the Maximum memory option is selected incorrectly. To fix this, follow these steps:
1.Click Start Start button, type msconfig in the Search programs and files box, and then click msconfig in the Programs list.
2.In the System Configuration window, click Advanced options on the Boot tab.
3.Click to clear the Maximum memory check box, and then click OK.
4.Restart the computer.