i would expect the laptop to beep when the ram is removed and powered on, ,,,,,,but i,m not familiar with this model,,
a hardcore reset seems my only option today,,,,
i also have an nec m300 2ghz , which has a intermittant ram slot fault,,poor contacts,,,this laptop beeps when the ram makes poor contact with the slot,,,,
thats why i bought this d7830 laptop off ebay as complete, but "untested",,,,,,,,,,,,,,oh dear