What Steve said.

Also, remember that the number of ports is the number licensed, not necessarily the number of blank LEDs on the front.

After a start-up or reboot, the MEM card will keep trying to boot, but it can't boot until it finds its ports. It will do this independently of the Main Control Card and the Bay Control Card, which will be bringing up ports one card at a time. So the MEM will probably reboot itself and cycle three, four, maybe five times before it finds its ports. If it hasn't stopped rebooting within, say twenty minutes, THEN check programming and check to see if you may have an out-of-box failure.