On Saturday 02 July 2011 15:45:11 Robert Heller wrote: > At Sat, 02 Jul 2011 14:52:27 +0200 CentOS mailing list <centos at centos.org> wrote: > > Emmanuel Noobadmin wrote: > > >> It seems to me that it should be possible > > >> to have a simple, torch-battery operated, system > > >> which will keep the machine alive long enough > > >> to make a graceful exit. > > > > > > The problem > > > with your idea is that you'll need a DC to AC inverter that can handle > > > the output current required by your server and something to hold the > > > batteries (you'll need more than one because attempting to draw a huge > > > current from a normal battery will either kill it or at the very least > > > cause it to have a shorter than expected capacity) and everything > > > together, it's probably going to cost more in both money and time to > > > have this thing. > > > > I'm sure you are right, as I know nothing at all about power supplies. > > But surely computers actually use DC, > > so couldn't my torch-battery device just supply the PC components > > directly? > > A PC uses several *different* DC voltages: +12, +5, +3.3, and several > others and they need to be *precise*. Some of these are not an exact > multiples of the standard 1.5V Carbon-Zinc cells typicaly used in torch > batteries. I wonder, how is this issue solved in laptops? They use only one DC battery, typically with a single voltage output, AFAIK. Best, :-) Marko