Turn on the computer and you get a long beep followed by two short beeps a pause the repeats. The mother board is a Asus A84-SLI Delux

HI there..
1 long beep followed by two short beeps..
this Indicates a video error has occurred and the BIOS cannot initialize the video screen to display any additional information..
cause could be anything...
here are few - connections not connected or connected properly recent electrical storm caused a surge that damaged computer other hardware issues.. failing hardware device
solution (please note this is a labourious process)
first thing we need to isolate the problem.
remove any hard ware which is recently attached. remove external harddrives ....
open the cabinet.. reseat all the cables.. if it still gives you the same result then i am afraid could be a hardware problem...