I am not responsible if your devices send you back in time, explodes, implodes, bricks or flies into space from the use of any software I put up.


Monday, March 16, 2009

Power Savings With Power Plan

After using CPU-Z for a while you will notice that the CPU Core Voltage is actually not a constant value

For my AMD Turion X2 RM-72 Processor (Differs according to Processor Model)
P-State 1 is 2.100GHZ @ 1.100V
P-State 2 is 1.025GHZ @ 0.950V
P-State 3 is 0.525GHZ @ 0.800V
This is because when Clock Frequency is reduced Processor no longer requires more power to maintain stability. This is the main operating principal behind Quiet & Cool Technology

<--Credit to ComputerBase.de-->

If you check the diagram above you will notice while there are 3 P-States for RM & ZM Processors, there are only 2 available to QL & SI Processors.

Hence this indicates during idle RM & ZM Processors save more power than QL & SI Processors as they are able to go into deeper, more power saving P-States.

Hence if you are thinking about getting AMD Powered Laptop look out for ZM & RM Processors only and don't go for QL Processors since QL Processors are similarly priced for poorer Power Savings.

To take full advantage of the AMD Processor Power Saving Capability in Vista
You should create 3 Power Plans

Set Maximum Processor state to 100%, 50% and 25% for 3 different Power Plans
This will cap the Maximum CPU Voltage to 1.100V , 0.950V and 0.800V respectively
(This is for reference purposes only as different CPU has different Voltage Levels)

For example when you are surfing the internet while running on battery you might want to choose power plan that caps voltage at 0.800V to save more power.

You can argue that the processor is already doing the throttling automatically hence there is no need to interfere however, occasional CPU spikes can occur to push the frequency. Therefore by limiting max frequency you are limiting the power usage explicitly.

Another advantage you will get is that the CPU Core temperature will fall below 50 degrees if you HWMonitor it

You may think 500MHZ will lag your system, but remember this is 500MHZ Dual Core Turion Processor.
Moreover on Acer Aspire 4530, the Windows Vista Desktop rendering is offloaded to the Nvidia 9100M G GPU hence there is little or no load on Vista as compared to any Intel Graphics Solution.

However do note when running different Applications consider the Processing Power requirements. Otherwise you might encounter slow performance.
Streaming video like youtube requires higher performance or you will encounter frame skips on the videos.

The above is for Windows Vista which supports more flexible and advance Power Settings

For Windows Xp you will need a third party program Speedswitch XP as suggested by AMD Forumer Turion64Ultra

As the instructions on SpeedSwitch Xp is available on it homepage I will leave the exploration of this third party software to people who are interested

No comments: