RAM problem

When I install some more Ram onto my MPC it does not seem to notice it...
Is anything I have to do to let it understand that I am adding more memory ?
thank for your help.

this i s really important.

usually when you install it the machine will automatically recognize it. could be that your ram is bad.

It's been awhile since I opened up my MPC... but make sure the ram is pushed all the way into the slots. I can't remember if they have latches to lock them in place like in a computer. Try that.