If he wants the computer to remain running for 20 minutes when power goes down then he'll either have to connect very little to it or get a rather hefty size battery. We purchased a number of Chloride units years back (may of the batteries are dead now) and the largest we have is 1200Va. We have both the computer and a 20" CRT connected to it and the longest it would hold up in a blackout was about 9 mins. Admittedly, an LCD screen requires less power so if he has one then this will help his up time. If your friend wants to hold up most of his workstation (computer, monitor/s, external hard drives, video capture devices etc) then the battery size will need to be taken into consideration. Cheers, Coj Rod Duncan <roduncan at telus.net> A good friend of mine lives on a rural property where their power grid is unstable. Sometimes it will wildly fluctuate on and off for a 1/2 dozen times before either going off or returning to their normal. I have recommended he get a reliable UPS battery backup system for his Mac run digital video studio. What he needs is protection from spikes, brownouts etc. with a reliable battery UPS system that will automatically kick into battery mode and then allow a "software controlled shutdown". While there are lots of battery UPS systems available. (I like Belkin for price performance) What software is available to allow an automatic shutdown in OSX? Most software is designed to automatically reboot the system and keep it up and running for servers etc. He just wants to be able to have it safely shut down from emergency battery power after a predetermined length of time, such as 20 minutes, if the main power doesn't return. Suggestions for software in OSX for this? There was/is older software for system 9. Too bad Apple didn't offer a timed shutdown option when running on battery power. Must be something out there. Thanks in advance. Rod -- _____________________________ Rod Duncan "Buy a Mac and be thought a fool or buy a Windows box and remove all doubt." Still virus free... and after all these years.