Greg Lindahl wrote: > On Thu, Apr 02, 2009 at 10:11:07AM -0400, Prentice Bisbal wrote: > >> Or it could be because they make motherboards that convert 12 VDC to 5 >> VDC on the motherboard. > > All Itanium and some other x86 boxes take a single 48V input to the > mobo. I talked to a mobo designer once and he claimed that there was > no power savings to be had doing this. Beats me, mon. > > -- greg
High-voltage, low-current lines do have less resistive losses than lower-voltage higher-current lines (Power loss = current^2 * resistance). That's why power transmission lines are very high voltages and low current. However, I would imagine this is a trivial amount at 12 VDC vs 5 VDC and the incredibly short distances the electricity travels on a PCB trace. Google claims that it saves power, so someone at Google must have obviously researched and measured this. -- Prentice _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
