Dell PowerEdge M820 Owner's Manual page 77

Environmental
Expanded operating temperature restrictions
For temperatures between 40 °C and 45 °C, de-rate
maximum allowable dry bulb temperature by 1 °C per 125 m
above 950 m (1 °F per 228 ft).
• Do not perform a cold startup below 5 °C
• Install only 87 mm wide heat sinks
• Do not install more than 40 DIMMs
• The following do not support expanded operating
temperature range:
– PCIe SSD
– Express flash
– LRDIMMs
– 130 W four-core processors
– Non Dell-qualified peripheral cards and/or
peripheral cards greater than 25 W
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