Before you get carried away installing the latest (6.4) version of DELL Open Manage Server Administrator on an older system its worth checking the OMSA docs and OMSA RAID compatibility list so you dont actually lose any functionality !
For example the highest version of OM that works with
- a DELL PE 1800 with PERC 4/SC raid controller or
- a DELL PE 2900 with PERC 6/i raid controller
is OM 6.1 with SMS 3.1
So instead of installing the latest OM you’ll need to chose the best version for your hardware from