Please, I had ASUS P5PL2 Mother-Board, with Pent.4 CPU 2.8 / 1 mb cash, it have 4 slots for RAMs, DDR2 SDRAM , it works fine with 1 mb RAM (2x 512 mb PC2-4200 DDR2) I upgrade to (2x 512 mb PC2-5300 DDR2 ) it works Fine, When I upgrade to (4x 512 mb PC2-5300 DDR2) which means 2 GB Ram, The Computer did not startup , even the Monitor is black, only the LED power is on. When I remove (2x 512 mb PC2-5300 DDR2) Left only 2 rams which are 1 GB, it works fine, SO, What is the problem here ???? Any Help Please welcome. My Opreting system is Win XP Media center. THANKS. Thanks alot