Intel 5100 Series Instruction Manual page 9

Introduction
Table 1-2. Terms and Descriptions (Sheet 2 of 2)
T The measured ambient temperature locally surrounding the processor. The ambient temperature should be
LA
measured just upstream of a passive heatsink or at the fan inlet for an active heatsink.
T The system ambient air temperature external to a system chassis. This temperature is usually measured at
SA
the chassis air inlets.
U A unit of measure used to define server rack spacing height. 1U is equal to 1.75 in, 2U equals 3.50 in, etc.
Dual-Core Intel® Xeon® Processor 5100 Series Thermal/Mechanical Design Guide
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