did you try with just the 4GB without the 2GB?
Yup. Already tried. Even wth only 4gb installed, the windows wont boot. Even changing the ram brands give no success. Sometimes bsod appear, smthing like'irql...less_or_equal'..so for now, the only solution is just add 2GB..but i want to max its ram to 8gb because i use wndws 7 64bit and i use my laptop to run photoshop and mny more.
So how do i solve this problem?