Quote: Originally Posted by
Nermin 
I did that a few days ago and it didnt show any errors and in the start it was all ok but now its shows just 3 GB..rr im so mad..
Right. Boot into your system BIOS (usually by repeatedly pressing the <DEL> during initial power on).
What does the BIOS report as "Installed Memory" and "Usable Size". There is a distinction between the two.
If "usable" is less than "installed", then there are perhaps some settings in your BIOS that have changed from what they aught to be?