HP Power Regulator for ProLiant servers

Figure 3 shows the same power and performance comparison for the DL385 G7 server. In this

comparison, if you don’t require the full performance range of the processors, Static Low Power mode

will give you the most power savings until you reach a performance utilization of about 45%. Above

this level, the Dynamic Power Savings mode begins to run the processors at the higher P-states to

maintain optimal system performance.

Figure 3. Power and performance comparison of the DL385 G7 server in Dynamic Power Savings mode (slow and

fast response time) and Static modes (Low Power and High Performance)

100

0 102030405060708090100

Performance (percent)

Power (percent)

Static Low Power mode provides

greatest power savings below 45%

Static High Performance mode

Static Low Power mode

Dynamic Power Savings mode (Slow response)

Dynamic Power Savings mode (Fast response)

You can draw several conclusions from these tests:

• Static High Performance mode delivers the highest performance at every performance interval up to

maximum processor performance (100%), and it always consumes the most power.

• Static Low Power mode gives you the best power efficiency below a certain performance level (the

level varies by processor type and maker). Static Low Power mode also gives you the best overall

power efficiency if you don’t require the full performance of the processor. The mode can provide

significant power savings with little or no degradation in system performance at these lower

utilization levels. Figures 2 and 3 show the processor performance limits for Static Low Power mode

in each test.

• Because Dynamic Power Savings mode lets the firmware determine the best performance-to-power

level, it achieves lower power consumption in low processor-utilization situations, and high

performance when the processor reports high levels of utilization. These characteristics give