I hate to drop this on you but you have a 6-9 year old system. If I were you, I'd stop putting money into your existing system, and start planning out a new one. At some point "upgrading" an outdated system is just a money pit that will go nowhere. Even a bottom-of-the-barrel entry level built today would yield to noticeably better performance and improved efficiency than your current system. What are you options financially?