User manual

conditions. Read additional restrictions in your product documentation.
Contact TOSHIBA technical service and support, refer to TOSHIBA support
section in Chapter 6, Troubleshooting for more information.
64-Bit Computing
64-bit processors are designed to take advantage of 32 and 64 bit
computing.
64-bit computing requires that the following hardware and software
requirements are met:
64-bit Operating System
64-bit CPU, Chipset and BIOS (Basic Input/Output System)
64-bit Device drivers
64-bit applications
Certain device drivers and/or applications may not be compatible with a 64-
bit CPU and therefore may not function properly.
Memory (Main System)
Part of the main system memory may be used by the graphics system for
graphics performance and therefore reduce the amount of main system
memory available for other computing activities. The amount of main
system memory allocated to support graphics may vary depending on the
graphics system, applications utilized, system memory size and other
factors.
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.
Computers configured with a 64-bit operating system can address 4 GB or
more of system memory.
Battery Life
Battery life may vary considerably depending on product model,
configuration, applications, power management settings and features
utilized, as well as the natural performance variations produced by the
design of individual components. Published battery life numbers are
Satellite U840W series
User's Manual C-2