Kevin Tofel of jkOnTheRun and I have been emailing back and forth over the last few days to coordinate a series of battery tests on the Asus Eee PC 1000H and MSI Wind with the 6 cell battery. Both computers have similar specs including a 10 inch display, 1.6GHz Intel Atom CPU, and 80GB hard drive. And both come with a 6 cell battery, although the Asus battery is 6600mAh while the Wind ships with a 5200mAh battery.

But it turns out that it’s difficult to make an apples to apples comparison because each notebook comes with its own power management features. The Asus Eee PC 1000H has a utility that lets you alternate between 1.2GHz, 1.6GHz, and 1.7GHz. At least I think that’s what it does. Unfortunately it displays the slightly less informative names “power saver,” ” high performance,” and “super high performance.”

The first time I ran my battery test using power saver mode, I got 265 minutes, but I later realized Windows XP was turning off the display after 10 or 15 minutes. I later ran the same test with no Windows XP power management features turned on and got 235 minutes. Kevin, on the other hand ran his first test with the MSI Wind running at full speed, so I tried one more test at high performance (1.6GHz) and got 199 minutes. Kevin decided to try another test using the awkwardly named “turbo” feature on his MSI Wind which underclocked his computer to 800MHz.

So how do the two computers stack up against one another in terms of battery life? On the closest we could arrange to an apples to apples test, the Eee PC 1000H laster for 3 hours and 19 minutes while running at 1.6GHz. The Wind got an extra 20 minutes and lasted for 3 hours and 39 minutes. It’s possible that the difference is due to subtle hardware differences between the two computers. Or it’s also possible that there was human error in the way we ran the tests. Either way, it’s not a huge difference, but the Wind definitely came out ahead here.

When running each computer using the manufacturer’s power saving mode, the Wind came out way ahead. At 800Mhz, Kevin’s Wind ran for 4 hours and 59 minutes, while my 1000H died after about 4 hours and 25 minutes when running at 1.2GHz. Of course, I suspect you’d get better performance on a machine running at 1.2GHz, but the difference might be marginal.

If all of these numbers seem low to you, keep in mind the fact that the Battery Eater test Kevin and I were running is designed to tax your CPU non-stop. If you spend most of your time surfing the web or writing documents, odds are youre CPU isn’t working as hard and you’ll get an extra hour or two out of the battery. Both Kevin and I estimate that we’ve been able to use our computers for 3 to 5 hours at a time without plugging them in, and I’d bet you could probably stretch that figure to 5 and a half or even 6 hours by dimming the screen a bit more and turning off WiFi if and when you’re not using it. Kevin says he thinks you might even be able to use a Wind for 7 hours if you can live with the performance hit that comes with running the computer at 800MHz.