Fan Speed Control Algorithm With T Data; Ambient Data; Fan Response Without T - Intel Core i7-800 Specifications

Sensor Based Thermal Specification Design Guidance
are less than T
from T
CONTROL
control algorithms.
As the processor workload continues to increase, the DTS value will increase and the
FSC algorithm will linearly increase the fan speed from the 2300 RPM at DTS = -20 to
full speed at DTS value = -1.
Figure 7-6.

Fan Response Without T

7.4.2 Fan Speed Control Algorithm with T
In a system where the FSC algorithm has access to the T
capable of using the data the benefits of the DTS thermal specification become more
striking.
As will be demonstrated below, there is still over cooling of the processor, even when
compared to a nominally ambient aware thermal solution equipped with a thermistor.
An example of these thermal solutions are the RCFH7-1156 (DHA-A) or the boxed
processor thermal solutions. This over cooling translates into acoustic margin that can
be used in the overall system acoustic budget.
In this example the following assumptions are made:
• T
AMBIENT
• The same Thermal Solution designed / validated to a 40 °C environment as used in
the example in
• T
CONTROL
• FSC device has access to T
• Reference processor thermal solution (RCFH7-1156 (DHA-A))
• Below T
Thermal/Mechanical Specifications and Design Guidelines
. For simplicity, the graph shows a linear acceleration of the fans
CONTROL
- 10 to T as has been Intel's guidance for simple fan speed
CONTROL
AMBIENT
= 35 °C
Section 7.4.1
= -20
AMBIENT
the fan speed is slowed down as in prior products
CONTROL
Data
AMBIENT
AMBIENT
data
Data
information and is
55