When the Macintosh Portable is in a "Sleep" or "Shut Down" state, having
1MB of RAM draws 4.5mA, and adding another 1MB in the RAM expansion-card
slot raises the total draw to 6mA. Though we haven't tested the longevity
of the battery with the additional 1MB of RAM, it should have a very
minimal effect.
When the Macintosh Portable is active, the RAM power requirements are
approximately 20 to 35mA with 1MB or 2MB of RAM installed, respectively.
This power draw is relatively insignificant, a mere increase of 15mA, as
compared to the 200mA the logic board draws, 50 to 70mA for the display,
and 700mA for the hard drive.
Of course, this applies to Apple's Portable RAM expansion, because
third-party RAM boards may use different kinds of RAM with different power
consumption characteristics.