AMD Richland

15 AMD “RICHLAND” APU | HOT CHIPS 25 | PRAVEEN DONGARA | AUGUST 2013
Control Loop (similar to above)
INTELLIGENT BOOST
MOTIVATION
Activity from
Cac Monitors
Power
Calculation
Temp.
Calculation
P
calculated
Freq
V
T
calc
T
calc
<>
Max
Temp.?
Limit
P0
P1
Pboost2
...
New Operating F, V
T
calculated
Temp.
of other
TEs
*
Boost Scalar
Pboost0
On-die Temperature Sensor Readings
Pboost1
cTDP Scalar
Control Loop (similar to above)
 CPU and GPU share a cooling solution, which means that when one burns more power, the other must burn
less.
 Without Intelligent Boost:
• Each thermal entity uses the following approach:
• CPU and GPU entities raise frequency (and power) as high as possible, within their thermal/other
limits (or until the highest Pstate is reached).
• Computational efficiency (whether freq translates well to perf) is not considered.
• Power and frequency that CPU ends up with may be more than is needed for GPU-centric workloads.
• Can affect power efficiency (performance/watt).
Without Intelligent
Boost
Each control loop
independently
consumes power
and raises
frequency