I really like subnotebooks (or sub-notebooks or subnotes, as you prefer), yet there are still far fewer to choose from than larger-sized laptops. The June, 2006 issue of Laptop Magazine had a cover story entitled "Featherweight Champs", which compared six notebooks under 4 lbs. They crowned one a "winner," but, as usual, it wasn't clear to me precisely why it won.
So, to help escape the problems inherent with such subjective methods, I'd like to propose a new metric for comparing small notebooks -- the GearBits Subnotebook Scale (or GSS).
The concept is pretty easy: compare some good aspects with some bad aspects and derive a numeric score as a ratio of the good to the bad.
Good Things (numerator):
- Screen resolution (in megapixels)
- Screen size (diag., in inches)
- Optical drive on-board (Yes = 3, No = 1)
- Battery life (actual, with wireless on, in hours)
- Keyboard pitch (horizontal, in millimeters)
Bad Things (denominator):
- Size (square root of width X depth)
- Thickness (average thickness, in in.)
- Weight (in lbs., as configured above)
Calculation Example: Panasonic Toughbook W4 (shown)
(1024x768/1000000) • 12.1 • 3 • 6 • 19 3254.4
-------------------------------------- = ------ = 88.4
(10.6x8.3)1/2 • 1.4 • 2.8 36.8
Here is how some of the more popular subnotes compare:
| Model | Screen Res | Screen Size | Optical | Batt. Life | K/B Pitch | Size | Thick | Weight | GSS Score |
| Panasonic Toughbook Y4 | 1400 x 1050 | 14.1 | Yes (3) | 5 | 19 | 12.2 x 9.6 | 1.6 | 3.4 | 100.3 |
| Sony VAIO TX750P/B | 1366 x 768 | 11.1 | Yes (3) | 4 | 17 | 10.7 x 7.7 | .98 | 2.8 | 95.4 |
| Panasonic Toughbook W4 | 1024 x 768 | 12.1 | Yes (3) | 6 | 19 | 10.6 x 8.3 | 1.4 | 2.8 | 88.4 |
| Fujitsu LifeBook P7120 | 1280 x 768 | 10.6 | Yes (3) | 5 | 18 | 10.3 x 7.8 | 1.35 | 3.4 | 68.4 |
| Toshiba Portege R200 | 1024 x 768 | 12.1 | No (1) | 5 | 19 | 11.2 x 9 | .54 | 2.7 | 61.8 |
| Dell Latitude X1 | 1280 x 768 | 12.1 | No (1) | 3.1 | 18 | 11.3 x 7.8 | .98 | 2.5 | 28.9 |
Sure, the GSS is not comprehensive. For example, it doesn't differentiate a basic internal DVD/CD-RW "combo" drive from a full-blown internal 16X Dual-Layer DVD-R/W -- either would contribute the same to a laptop's GSS score. So, consider the GSS just as a starting point...feel free to customize it as you see fit, depending on your priorities and needs. Here's a pre-made Excel GSS calculator if you want to tweak the GSS for your own use.
I would suggest that for every "must have" feature beyond those listed above (e.g., Bluetooth), add 20 (or less) to the model's GSS score, depending on the feature's value to you. For example, if you deem Bluetooth to be an indispensible feature, give it a bonus of 20 points -- the Fujitsu P7120 above would have a revised score of 96.3 rather than 76.3, making it a top contender for you. Just remember to add similar adjustments to other laptops with the same feature(s). Sum up these add-ons and compare the revised GSS scores.
And while I designed the GSS to rate subnotebooks specifically, there's no reason you couldn't plug in the specs on any laptop. Just remember that it will likely favor smaller, lighter laptops over bigger, heavier ones even if the larger units offer better performance.
So, how does your laptop score?
Update: A couple of friends with Mac laptops emailed me specs (see table below) -- the GSS seems to work regardless of laptop size (or OS ;-), but it does tend to favor smaller notebooks.
| Model | Screen Res | Screen Size | Optical | Batt. Life | K/B Pitch | Size | Thick | Weight | GSS Score |
| Apple Powerbook G4 | 1280 x 854 | 15.2 | Yes (3) | 2.5 | 19 | 13.7 x 9.5 | 1.1 | 5.6 | 33.7 |
| Apple MacBook Pro | 1680 x 1050 | 17 | Yes (3) | 3.75 | 19 | 15.4 x 10.4 | 1 | 6.8 | 74.5 |