Intel Celeron Processor in the 478-Pin Package at 1.80 GHz Datasheet

Datasheet 95
Intel
®
Celeron
®
Processor in the 478-Pin Package
8.3.2 Variable Speed Fan
The boxed processor fan will operate at different speeds over a short range of internal chassis
temperatures. This allows the processor fan to operate at a lower speed and noise level, while
internal chassis temperatures are low. If internal chassis temperature increases beyond a lower set
point, the fan speed will rise linearly with the internal temperature until the higher set point is
reached. At that point, the fan speed is at its maximum. As fan speed increases, so does fan noise
levels. Systems should be designed to provide adequate air around the boxed processor fan
heatsink that remains below the lower set point. These set points, represented in Figure 40 and
Table 38, can vary by a few degrees from fan heatsink to fan heatsink. The internal chassis
temperature should be kept below 40ºC. Meeting the processor’s temperature specification (see
Chapter 6.0) is the responsibility of the system integrator.
Figure 39. Boxed Processor Fan Heatsink Airspace Keepout Requirements
(Side 2 View)
Figure 40. Boxed Processor Fan Heatsink Set Points