Using RMClock

Note: Because of the advanced nature of the program, a modicum of computer knowledge is assumed for this guide. THIS IS NOT A PROGRAM FOR NEWBIES.

In this guide we will cover the basics of using RMClock to tweak laptop battery usage (and heat generation) on Windows 2000 and beyond systems. The version used here is Version 2.2 RC3, however it is essentially the same as the current (14/11/06) official release, 2.15. The platform used for this guide is an early Centrino platform, equipped with a Intel Pentium M at 1.6GHz and 855PM chipset.

RMClock can be used with a variety of processors, supporting all processors newer than the Pentium 4 for Intel platforms and processors newer than the AMD Athlon XP for AMD processors. Obviously not all platforms support the same level of functionality, and this article is written with mobile platforms which allow for multiplier selections in mind (which is almost all mobile platforms except for the Celeron M)

The Athlon XP platform has a few quirks. Settings are generally chipset dependent, and these are not covered here (since the author has not dealt with a system that could be usefully tweaked).

Because RMClock is based on software, there is no way to exceed the boundaries of the hardware. Whilst it can be used to aid overclocking, that is not the primary purpose of the program, and thus this article does not deal with using this program for this purpose.

Download RMClock from the official website at http://cpu.rightmark.org/products/rmclock.shtml. There are two installtion options that you can use, either the guided installer or the rar archive. For the installer, follow the instructions as a normal installer. For the rar archive, extract all its contents to a suitable place.

Double click either the executable file or a shortcut that has been created on the desktop or start menu, depending on your installation preferences. As with other programs shortcuts can be created to the executable from places where the user sees fit.

Upon successful installation and execution, the user should be greeted with this dialogue:

The information will vary depending on your processor and latter configuration.

These are all line graphs that show the changes in the various aspects of your computers operation. CPU load and OS load differ in that CPU load (green) is the actual percentage of clock cycles that are being taken up in the processor at the selected speed. OS load shows load as though the processor was full speed all the time (and should correspond with the load shown in Task Manager)

CPU Core temprature in the screenshot is N/A as the Pentium M does not have a supported on core thermal diode. The Intel Core and beyond processors do, as should the AMD Athlon 64 and beyond processors.

This controls wheter the CPU can change to intermediate frequencies when changing speeds. The options are to allow transitions to intermediate frequencies or not.

Multi-Core CPU Load Determination Method (here disabled):
Controls how the system load is calculated in RMClock in multicore systems (such as Core Duo) Disabled here as the author’s system is not multicore.

Determines RMClock’s behaviour when entering Stanby/Hibernate. The menu has a selection of profiles (explained later)

This selects if either the OS or RMClock determines what speed to switch to. For Centrino and other mobile platforms, OS management is recommended.

This creates a process which takes up all of the remaining idle CPU cycles that would have normally been used by the System Idle process. This is required on some systems where RMClock cannot control the CPU speed in normal circumstances. This will also result in the Task Manager displaying 100% load. RMClock will display the correct load.

This creates an alert when the CPU reaches hardwired thermal limitations and begins “throttling”, which is the reduction of the CPU’s performance and speed to curb the production of heat.

These options control what RMclock does in the event that it is closed or management is turned off (e.g “no management” profile is used) You can choose what speed and voltage will be set upon these events manually, or automatically either by those found at program startup or the CPU’s hardwired defaults.

These control the behaviour of the programs dialogues, taskbar/tray icons and the like.

Determines the profiles which are automatically selected whent the computer enters battery or AC
power.

CAUTION - INCORRECT SETTINGS HERE COULD DAMAGE YOUR COMPUTER.

This is the list of multiplier and voltage combinations (also known as “P-States”) that are available. The checkbox enables or disables the particular setting. To set a VID, click on the index entry and then use the drop-down box entitled “VID Select” to choose the voltages. Depending on the system in question, some voltages may not be available. The “Auto-adjust intermediate VIDs” checkbox allows the voltages for the P-states in between the highest and lowest (in this case, indices 1-8) to be scaled according to the highest and lowest settings. Selecting lower voltages equal longer battery life, however too low and your computer will become unstable and crash. (and too high will see your computer in an unglamorous premature end to its life)

In profiles we can set the voltages (VIDs) and multipliers (and hence frequency, FIDs). Of the four profiles, No management does not allow you to set anything (hence the name), Power Saving and Maximal Performance allow you to set only one Index speed (logically you would choose the fastest and slowest) and Performance On Demand allows you to select as many Indicies the user sees fit, and the program will choose them when the load warrants its use.

This is the profiles page. The profile selected here is Performance on Demand, however all profile pages are the same layout. The free version does not allow for additional custom profiles. The AC Power and Battery tab are the same in layout however as the title suggests, the tabs control how RMClock acts when this profile is activated depending upon the power source.

This checkbox allows the variation of frequencies as determined by the main table. Much like the main table, the checkbox on the index enables and disables that particular frequency selection.

The On Demand Clock Modulation (ODCM) table works much the same as the PST table. ODCM essentially only allows a certain percentage of clock cycles to be used for processing. It’s energy use reduction benefits are limited, and is more suited to heat reduction. The processor does not physically run at a slower speed.

As the CPU speed changes, depending on your processor there will be a lockout time when this occurs,
and the system will feel less responsive. This drop-down box basically sets how quickly RMClock pre-
empts system load and switches to a higher frequency.

This is essentially the Windows Power Scheme settings. The Override checkbox must be selected to use
this, and RMClock will adjust the settings depending on how they are set in the profile.

In order to this, download install Prime95 (Hardware Stress Testing, Prime95). Prime95 will place as high as stress as possible on the CPU component.

Set up one of the single speed profiles (either Maximal performance or Minimal performance) to the P-State you want to set a VID for.

Start Prime95 (two instances if your system is dual core, more if you happen to have more cores) , and set RMClock to that particular profile. Now go back to the main table and incrementally reduce the VID, allowing prime to run for about 5 minutes until Prime95 reports an error. Once this occurs, set the voltage one increment higher, and prime for an extended period of time, and check for errors. It is generally suggested to allow a leeway of two VID steps to ensure maximum stability.

For quick results, repeat for the lowest and highest P-State and check the Auto adjust checkbox, whereby the middle VIDs will be automatically scaled.

You can repeat this for every P-state available to without auto-adjust to get the lowest possible voltages for every frequency. The voltages in the authors case did not scale linearly.

N.B: Some processors may have P-states which show but don’t actually work. Remember to monitor the main page of RMClock and use a third party program such as CPU-Z to ensure that the speed and voltage you want is indeed the speed that is being set.

This page shows the information about the charge level power consumption, and ageing information as recorded by the battery’s inbuilt logic. Some systems will only show specific amounts of data (e.g on the author’s system, the power consumption is a constant value)

The checkboxes determine the behaviour of the battery icon in the taskbar.

These settings are CPU dependent. Due to this, these settings will not be covered here.

In addition, incorrect settings may lead to system instability, so if you do not know what you are doing it is suggested that you leave these settings as they are.

RMClock Utility

Hardware Stress Testing