Introduction
VL-EPICs-36 Reference Manual
4
Thermal Considerations
CPU
D
IE
T
EMPERATURE
The CPU die temperature is affected by numerous conditions, such as CPU utilization, CPU
speed, ambient air temperature, air flow, thermal effects of adjacent circuit boards, external heat
sources, and many others.
The CPU is protected from over temperature conditions by several mechanisms.
The CPU will automatically slow down by 50% whenever its die temperature exceeds 105° C.
When the temperature falls back below 105° C, the CPU resumes full speed operation.
As a failsafe, if the CPU die temperature climbs above 115° C, the CPU will turn itself off to
prevent damage to the chip.
Note:
Intel does not warrant their CPUs in the event of this occurrence.
M
ODEL
D
IFFERENCES
VersaLogic offers both standard and extended temperature models of the VL-EPM-35. The basic
operating temperature specification for both models is shown below.
VL-EPICs-36S: 0° C to +60° C free air, no airflow
VL-EPICs-36E: -40° C to +85° C free air
To reliably function at extreme temperatures the extended temperature model specifications
deviate from the standard model in the following ways:
The DRAM interface is slowed. PC3-6400 memory runs at 600 MHz. PC3-8500
memory runs at 800 MHz.
The DRAM refresh rates are doubled.
The Front Side Bus speed is reduced to 800 MHz.
Maximum processor speed is limited to 1200 MHz.
The graphics core is limited to 400 MHz.
