Owners Manual

Table 16. Operating temperature de-rating specifications
Operating temperature
de-rating
Specifications
Up to 35°C (95°F) Maximum temperature is reduced by 1°C/300 m (1°F/547 ft) above 950 m (3,117 ft).
35°C to 40°C (95°F to
104°F)
Maximum temperature is reduced by 1°C/175 m (1°F/319 ft) above 950 m (3,117 ft).
40°C to 45°C (104°F to
113°F)
Maximum temperature is reduced by 1°C/125 m (1°F/228 ft) above 950 m (3,117 ft).
Standard operating temperature
Table 17. Standard operating temperature specifications
Standard operating temperature Specifications
Continuous operation (for altitude less than 950 m or 3117
ft)
10°C to 35°C (50°F to 95°F) with no direct sunlight on the
equipment.
Thermal and acoustics
The system's thermal management delivers high performance through optimized cooling of components at the lowest fan
speeds across a wide range of ambient temperatures from 10°C to 35°C (50°F to 95°F) and to extended ambient temperature
ranges. These optimizations result in lower fan power consumption which translate to lower system power and data center
power consumption.
Thermal design
The thermal design of the system reflects the following:
● Optimized thermal design: The system layout is architected for optimum thermal design. System component placement and
layout are designed to provide maximum airflow coverage to critical components with minimal expense of fan power.
● Comprehensive thermal management: The thermal control system regulates the system fan speeds based on feedback from
system component temperature sensors, as well as for system inventory and subsystem power draw. Temperature
monitoring includes components such as processors, DIMMs, chipset, system inlet air ambient, hard disk drives, NDC, and
GPU.
● Open and closed loop fan speed control: Open loop fan control uses system configuration to determine fan speed based on
system inlet air temperature. Closed loop thermal control uses temperature feedback to dynamically adjust fan speeds based
on system activity and cooling requirements.
● User-configurable settings: With the understanding and realization that every customer has a unique set of circumstances or
expectations from the system, in this generation of servers, we have introduced limited user-configurable settings in the
iDRAC9 BIOS setup screen. For more information, see the Dell EMC PowerEdge system Installation and Service Manual on
Dell.com/Support/Manuals and “Advanced Thermal Control: Optimizing across Environments and Power Goals” on Dell.com.
● Cooling redundancy: The system allows N+1 fan redundancy, allowing continuous operation with one fan failure in the
system.
● Environmental Specifications: The optimized thermal management makes the R940xa reliable under a wide range of
operating environments.
Expanded operating temperature restrictions
● The operating temperature is for a maximum altitude of 950 m for fresh air cooling
● No cold start-ups below 5°C due to hard drive constraints
● Apache Pass DIMM, NVDIMM, PCIeSSD and NVME are not supported
● GPGPU configuration are not supported
● LRDIMM > 32 GB are not supported in x4 socket configurations
● DCPMMs are not supported.
Technical specifications
15