Standby Current Requirements - Intel D850GB Technical Product Specification

Intel Desktop Board D850GB Technical Product Specification

2.11.3 Standby Current Requirements

CAUTION
If the standby current necessary to support multiple wake events from the PCI and/or USB buses
exceeds power supply capacity, the D850GB board may lose register settings stored in memory,
etc. Calculate the standby current requirements using the steps described below.
Power supplies used with the D850GB board must be able to provide enough standby current to
support the Instantly Available (ACPI S3 sleep state) configuration as outlined in
Table 52 below.
Values are determined by specifications such as PCI 2.2. Actual measured values may vary.
To estimate the amount of standby current required for a particular system configuration, standby
current requirements of all installed components must be added to determine the total standby
current requirement. Refer to the descriptions in Table 52 and review the following steps.
1. Note the total D850GB board standby current requirement.
2. Add to that the total PS/2 port standby current requirement if a wake-enabled device is
connected.
3. Add, from the PCI 2.2 slots (wake enabled) row, the total number of wake-enabled devices
installed (PCI and AGP) and multiply by the standby current requirement.
4. Add, from the PCI 2.2 slots (nonwake enabled) row, the total number of wake-enabled devices
installed (PCI and AGP) and multiply by the standby current requirement.
5. Add all additional wake-enabled devices' and nonwake-enabled devices' standby current
requirements as applicable.
6. Add all the required current totals from steps 1 through 5 to determine the total estimated
standby current power supply requirement.
Table 52.

Standby Current Requirements

Instantly Available Current
Support (Estimated for
Integrated Board Components)
Instantly Available Stand-by
Current Support
•
Estimated for add-on
components
•
Add to Instantly Available
total current requirement
(See instructions above)
Note: Dependent upon system configuration
74
Description
Total for D850GB board
PS/2 ports (Note)
PCI 2.2 slots (wake enabled)
PCI 2.2 slots (nonwake enabled)
WOL header
CNR (Note)
USB ports (Note)
Standby Current
Requirements (mA)
300
345
375
20
525
375
500