User’s Manual 3-4
Hardware, Utilities and Options
Power
If your computer is configured with more than 3 GB memory, the memory
might be displayed as approximately 3 GB only (depending on the
computer’s hardware specifications).
This is correct because the operating system usually displays the available
memory instead of the physical memory (RAM) built into the computer.
Various system components (like the video adapter’s GPU and PCI
devices like Wireless LAN, etc.) require their own memory space. Since a
32-bit operating system cannot address more than 4 GB of memory, these
system resources overlap the physical memory. It is a technical limitation
that the overlapped memory is not available to the operating system. Even
though some tools might display the actual physical memory built into your
computer, the memory available to the operating system will still be
approximately 3 GB only.
Legal Footnote (Memory (Main System))*3
For more information regarding Memory (Main System), please refer to the
Legal Footnotes section in Appendix G or click the *3 above.
Battery pack The computer is powered by one rechargeable
lithium-ion battery pack.
Legal Footnote (Battery Life)*4
For more information regarding Battery Life, please refer to the Legal
Footnotes section in Appendix G or click the *4 above.
RTC battery The internal RTC battery backs up the Real Time
Clock (RTC) and calendar.
AC adaptor The AC adaptor provides power to the system
and recharges the batteries when they are low. It
comes with a detachable power cord which will
either have a 2-pin or 3-pin plug enclosure.
As the AC adaptor is universal, it can receive a
range of AC voltages from 90 to 264 volts,
however you should note that the output current
varies among different models. Using the wrong
adaptor can damage your computer. Refer to the
AC adaptor section in Chapter 2, The Grand
Tour.