disks have seek times of more than 3ms, while flash memory can seek in a fraction of 1ms. On the other hand, for sustained access to a large chunk of data, SSD is only about 10 percent faster than a hard drive, while it is 30 percent slower when writing data.

For the average UMPC user with only flash memory, the likely outcome of all this is that boot times—which load a lot of small files—are improved compared to laptops with hard disks. But many general tasks, like Web browsing or working with large files, may be slower compared to

There just isn’t that much space for batter-
ies without adding size and weight.

The XO has delivered modestly better performance in real world use, pushing four-to-five hours on average. In “e-book” mode, where the XO is used as a tablet reader with the screen set to monochrome mode, the battery can last much longer, as much as double normal usage. But these gains come at the cost, in part, of a slower machine overall.

Aftermarket batteries for the Eee
PC are available, and run between
$50-$100, extending battery time to as

umPCs are selling because users are willing
to sacrifice performance for simplicity
and mobility. But the computer industry’s
natural instinct is to offer more.

hard disks because the write penalty will
often outweigh the seek advantage. Of
course, to UMPC buyers, less really
is more. Less storage capacity and less
speed also means less weight and less
power, highlighting the priority shift that
UMPCs represent.

Long Live the Battery, or Not

Of all the features that make an ultra-mobile PC, well, ultra-mobile, battery life remains the Achilles heel. In real world use, both the Eee PC and Classmate PC have been criticized for sub-three hour battery performance. It’s not difficult to find a conventional laptop that offers significantly longer usage off the juice.

In absolute terms, these dwarf laptops aren’t major power hogs. The Eee PC 701 draws between 14 to 18 watts in use, compared to an average of 70 watts for the typical laptop. But UMPCs are small.

much as seven hours. But the longest running batteries require extra cells (six compared to four for the Eee PC), which means adding bulk and a possibly awkward “battery bump” to the UMPC’s form factor.

Tickling the (Tiny) Ivories

The keys on a UMPC keyboard are small. It is natural to wonder won’t it be difficult to type on these things? The popular answer, by and large, is “yes.” Of course, “hard” varies from person to person and facility improves with practice.

LaptopMag.com performed a thoroughly unscientific test among several staffers, first measuring their word-per-minute rates on a full-size laptop. When rated on the Eee PC, the fastest typists saw their performance drop nearly in half. But typing on the HP Mini-Note’s keyboard, advertised as 92 percent of