These are mainly measured figures on some of the Macs we've owned, plus a few submitted by friends.
Macs are generally better on power than equivalent PCs. This is mainly due to the much lower power consumption of the processor itself. PowerPC processors use anywhere from 10 to 20% of their Pentium equivalents. Apple also seems to be more concerned with power consumption than many PC vendors. Flat panel iMacs have very low consumption because of their LCD screens.
|Apple||LC||68000 @ 16MHz||CPU only||18w||
|Apple||LC III||68030 @ 25/50MHz||CPU only||20w||
|Apple||LC 575||68030 @ 33/66MHz||All in one - includes Trinitron monitor||58w||Low power usage; great screen||SR|
|Apple||Power Mac 6100/66 DOS Compatible||601 @ 66MHz; 486 @ 66MHz||Including 14'' monitor, modem||140w||Apple Hi-Res RGB monitor, Global Village 33.6k modem||SR|
|Apple||Power Mac 7600/132||604 @ 132MHz||CPU only||75w||Normal||SR|
|Apple||Power Mac 9600/233||604e @233MHz||Driving extra PCI hardware, 2 drives, CPU only||95w||Normal||AMW|
|Apple||iMac - Model 406 (Rev C)||G3/750 @ 266MHz||All in one - includes monitor||100w||Normal||AMW|
|Power Computing||PowerCentre 120||604 @ 120MHz||CPU only||65w||Normal||AMW|
|Apple||PowerMac G4 (MDD)||2 X G4 @ 1.25GHz||CPU only. Extra hard drive & PCI card. OS X 10.2.6||140w||Normal||SR|
Consumption figures for sleep mode vary significantly with the operating system version. The later versions of OS 9 were excellent, whilst early versions of OS X were poor. The current version of X - 10.3.x is probably at least as good as, if not better than, the old MacOS.