Input Power Budget Derating - HP ProLiant DL380 Technical White Paper

HP ProLiant DL380 Generation 3 Server High-Density Deployment
If a deployment plan limits the future expansion beyond certain configuration options, adjustments
Input Power
can be made to the expected input current and thermal requirements of the servers.
Budget Derating
To derate the input power, start with the minimum configuration 1 from Table 3. Add the typical
power of the components included in the desired system configuration to calculate the derated power
budget. Typical input powers for various components are listed in Table 5.
Example
Assuming the desired server configuration is as follows, use Table 7 to calculate the derated power
budget using the typical power from Table 5.
Processors: 2 x 2.4 GHz
Memory: 4 x 512 MB
Storage: 2 x 18.2 GB
Table 7. Example of Derating Worksheet
Therefore, the new power budget for this configuration is 290 W (compared to the rated 565 W),
and the thermal dissipation is approximately 989 BTUs/hour (compared to the rated 1927
BTUs/hour).
The rated input power for the server power supply is 565 W. Therefore, the power budget for a
maximum configuration is 565 W, and the thermal dissipation will be approximately (565*3.41=)
1927 BTUs/hour.
This derated input power budget significantly reduces the power and thermal requirements for highly
populated racks, which reduces the number of PDUs for certain configurations. Fewer PDUs decrease
deployment time and lower costs. Costs for the facility electrical plumbing, data center floor
ventilation, and facility air conditioning installation can also be reduced.
IMPORTANT: HP strongly recommends verifying that the derated power budget satisfies all the
installation requirements, including future upgrade plans.
1. Start with the maximum rated input power for the base configuration
(1 processor, 2 DIMMs, 0 hard drives)
2. Add the typical power for the second processor
3. Add the typical power for the additional memory
4. Add the typical power for the additional storage
Typical power for the desired configuration
5. Calculate the thermal dissipation
Thermal dissipation for the desired configuration (in BTUs)
207 W
+40 W
+4.8 W (2.4 W per DIMM)
+ 38 W (19 per hard drive)
= 290 W
× 3.41
989 BTUs/hour
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