Underclock your Asus Eee PC for better battery life

If you own an Eee PC with a Celeron-M processor, here’s a useful tip. The Super-Hybrid Engine utility that’s designed for Asus’ Intel Atom-powered netbooks also runs on Celeron-M models, which means you can underclock your Eee PC 900 or 904 to get longer life from the battery.

Alas, this won't work on the Eee PC 701, since its Celeron-M processor is underclocked by default from 900MHz to 630MHz (though you can restore it to full-speed with these instructions).

We discovered this by accident during our testing of the Eee PC 904 when we installed the utility after forgetting that this laptop has a Celeron-M processor rather than an Atom. The Celeron-M isn’t quite as sophisticated in its power management as the Atom in its power-saving, and the chip runs at its stock 900MHz no matter what the laptop is doing (the Atom N270 drops to 800MHz when idle).

With the free Super-Hybrid Engine utility installed, however, it’s possible to underclock the Celeron-M from 900MHz to 630MHz by using its Power Saver mode. In our tests, this added around an hour to battery life, albeit at a negligible expense to performance. Incidentally, the utility also lets you overclock the processor to around 960MHz, but the performance gain is so small that it really isn’t worth bothering with.

The Eee PC 904 was perfectly stable with its Celeron-M processor underclocked in this way, but we haven’t tried it on the Eee PC 900 or 701, so YMMV. Since these have essentially the same specification though, we don’t anticipate any problems – let us know how you get on in the comments.

The utility is only available for Windows, so we're afraid that Linux users are out of luck. Here’s a direct link to the SupHybridEngine_XP_080619.zip file on the Asus server, or you can download it by going to the Asus support site and selecting downloads for the Eee PC 901 901/XP.