Datasheet
65
Thermal Management
5.2.2
Integrated Graphics and Memory Controller Thermal
Features
The integrated graphics and memory controller provides the following features for
monitoring the integrated graphics and memory controller temperature and triggering
thermal management:
•
One internal digital thermal sensor
•
Hooks for an external thermal sensor mechanism which can either be TS-on-DIMM
or TS-on-Board
The integrated graphics and memory controller has implemented several silicon level
thermal management features that can lower both integrated graphics and memory
controller and DDR3 power during periods of high activity. As a result, these features
can help control temperature and help prevent thermally induced component failures.
These features include:
•
Bandwidth throttling triggered by memory loading
•
Bandwidth throttling triggered by integrated graphics and memory controller
heating
•
THERMTRIP# support
•
Render Thermal Throttling
5.2.2.1
Internal Digital Thermal Sensor
The integrated graphics and memory controller incorporates one on-die digital thermal
sensor for thermal management. The thermal sensor may be programmed to cause
hardware throttling and/or software interrupts. Hardware throttling includes render
thermal throttling and main memory programmable throttling thresholds. Sensor trip
points may also be programmed to generate various interrupts including SCI, SMI,
INTR, and SERR. The internal thermal sensor reports six trip points: Aux0, Aux1, Aux2,
Aux3, Hot, and Catastrophic trip points in order of increasing temperature.
5.2.2.1.1
Aux0, Aux1, Aux2, Aux3 Temperature Trip Points
These trip points may be set dynamically if desired and provides a configurable
interrupt mechanism to allow software to respond when a trip is crossed in either
direction. These auxiliary temperature trip points do not automatically cause any
hardware throttling but may be used by software to trigger interrupts.
5.2.2.1.2
Hot Temperature Trip Point
This trip point is set at the temperature at which the integrated graphics and memory
controller must start throttling. It may optionally enable integrated graphics and
memory controller throttling when the temperature is exceeded. This trip point may
provide an interrupt to ACPI (or other software) when it is crossed in either direction.
Software could optionally set this as an interrupt when the temperature exceeds this
level setting.