Additional issues for 64-bit systems

Updated: July 8, 2008

This topic describes issues to be aware of when designing for 64-bit Windows systems.

APIC support

Under the "Designed for Windows" logo program for hardware, Itanium-based systems must include Streamlined APIC Advanced Programmable Interrupt Controller (SAPIC) support that complies with the 64-bit extensions defined in ACPI 2.0.


In addition to the hardware manageability guidelines defined in the Windows Hardware Instrumentation Implementation Guide, Itanium-based systems must implement hardware and firmware support for Itanium Machine Check Architecture.

USB devices

The system firmware must provide EFI boot support for USB keyboards, pointing devices, and hubs.

Parallel and serial devices

Itanium-based systems must not include legacy parallel ports. However, each system must provide a legacy serial port for developers and technicians to use as a debug port.

Multiprocessor support

For a system in which more than one processor can be installed, the system must employ those processors symmetrically; that is, all processors must be able to access all I/O buses and system memory, and cache coherency must be maintained. An Itanium-based system must include a Multiple SAPIC Description Table that complies with ACPI 2.0.

Console redirection

The system must provide support for redirection of all console I/O to the serial port. The driver for the serial console must be capable of supporting the capabilities documented in Extensions to the VT100 Terminal Definition. Note that unlike BIOS, EFI firmware must indicate which serial port is used for console I/O, and the configuration of that serial port through the console device path for the serial port as specified in EFI 1.0.

Other boot support

To ensure the system can boot from CD or DVD drives, the system must support the No Emulation mode in El ToritoBootable CD-ROM Format Specification, and the additional requirements defined in Section 16.2.2, "ISO-9660 and El Torito," in EFI 1.0.

Headless server support

The server editions of 64-bit Windows provide support for headless operating.

Windows Logo Program for Hardware

Requirements for the Microsoft Windows Logo Program for hardware related to sleep state support and wake support will not apply to Itanium-family systems submitted for Logo testing until operating system support is available. All other ACPI-related requirements remain applicable for Itanium-family systems that are submitted for "Designed for Windows" logo testing.

Related topics

Designing for 64-bit Windows
Windows hardware certification



Send comments about this topic to Microsoft