First, go download RightMark CPU Clock Utility (RMClock). It's the 5th box from the top of the page. Either the rar or the exe will work, they both install the same software.
Once you install it you'll see this.
If you don't see it after installing, it'll be in the task bar. It looks like a small cog or gear.
First thing you'll want to do is to check that RMClock does NOT start up with Windows. If it starts up every time on a bad setting, you'll have to hit safe mode to change it back. Think of it as a preemptive safety measure for now. Go to Settings on the left, and make sure "Run at Windows startup" is unchecked.
Before you start, remember: RMClock is a powerful and capable piece of software that can change the way your computer functions very easily. That can be both positive and negative. So as always, be careful. The steps I've taken here got me to a reliably working undervolted and underclocked machine, but not without a few scary hiccups along the way.
Let's begin.
The real meat of the program lives in the Profiles section on the left.
Mine is already configured, but it will work for explanation.
Step 1. Change P States and set Profiles:
The 5 boxes in the lower part of the main pane are P States, or power states. The FID is the multiplier of the cpu. For our cpu, the Athlon 1.2, our P States are rather limited. 4x equates to 800MHz and 6x equates to 1200MHz (1.2GHz or stock frequency).
The VID is the voltage the cpu will draw at each frequency (FID). This will take some tweaking, as every cpu and motherboard react differently. Mine are set to right above the lowest I could get them while still being stable under full load. 4x (800MHz) is at .6875v and 6x is at .8000v. These are actually one step above the voltage I tested full load at, for stability's sake.
The P States in between will automatically adjust, so you shouldn't have to change them at all or even select them.
The Profiles above the P States are simply choosing which profiles you'd like to use under which circumstances. So on AC power I have the Maximal Performance profile selected and on battery I have the Power Saver profile selected. Make sure to click apply on every pane you change settings on.
Step 2. Adjust Profiles to use the new P States:
Start by selecting on the left the profile you chose for AC Power. In my case it is Maximal Performance.
Select under AC Power "Use P-state transitions (PST)" and select the multiplier you'd like to use while plugged in. I chose 6x or 1.2GHz as battery life isn't a concern while sipping power from an outlet. Make sure to press apply on the bottom right. Your cpu should immediately undervolt to .8000v at 1.2GHz if successful. You can check it by hovering over the cog icon in the task bar. It should be colored (probably red). If not, go back and check your settings again. If it did, put some load on the processor to stability test it. If it crashes, don't panic, see Step 3.
Next select the Power Saving profile on the left.
Do the same thing on this pane. Under Battery check the use P-states box and select your desired multiplier. In my case I wanted maximum battery life so I went with the 4x or 800MHz box. Hit apply and that's it. Unplug the AC cable and check the task bar icon. It should change to green. Now run your favorite heavy application to put some load on the cpu. A favorite of mine is Hulu. Watch a show or two. If it crashes, no problem, just reboot and no harm done.
Step 3. If it crashes:
Say your rig crashed under load. Blue screens, lock ups, or anything not normal. It's usually a simple fix. If you have the bad clock generator that I have, these settings will work great. If you can overclock past 1.43GHz you have the better clock gen and your settings can get much more fancy. I'll just assume you have bad luck like I do and bought the bad clock gen equipped model.
Solution: raise the voltages. Go up one notch. If you used my settings: 4x @ .6875v and 6x @ .8000v, go up a single click on each back at the Profiles pane. My settings, like I said, are quite conservative and shouldn't need tweaking. I did get success at lower voltages so your mileage will vary if you go below my settings. I've read of people getting 4x 800MHz stable at .6000v but mine wouldn't do it.
Step 4. Cleanup:
If you're like me, you don't like a cluttered task bar. RMClock adds many little icons down there that annoyed me heavily. The Settings pane can fix that with a bit of tweaking. The Battery Info pane also helps. It allows you to disable Windows' battery icon to use RMClock's, which I recommend.
If you are successful with the P States, then go back and make sure RMClock is set to start with Windows, preferably minimized (in Settings).
This is only the tip of the iceberg with RMClock, it is a very advanced piece of software. It has more options than I'd feel comfortable checking off. I've seen far too many blue screens and lockups simply getting this far. jAnd that was ust by playing with voltages and settings. Again, be careful.
Good luck! If you have any questions or trouble, leave a comment and I'll check back pretty often.
