I followed these direction to upgrade my ram from 2 512MB chips to 2 1GB chips. They were simple, but I hit a snag somewhere because when I went to turn back on my computer the light on the slide just blinked several times and no start up ocurred. How do you know that the new RAM chips are in sufficiently? Do you have to press them in until they click or lock? Mine just slid in and are somewhat "loose" still.