That’s because the Core m3 processor inside the $899 is the only one that doesn’t use a fan for active cooling. As noted by iFixit in its Surface Pro 4 teardown, the entry-level model has an empty space next to its motherboard, where a fan likely resides in the Core i5 and Core i7 versions.
iFixit’s teardown also confirms that the Surface Pro 4 has a nine percent smaller battery than last year’s Surface Pro 3, at 5087 mAh instead of 5547 mAh. It seems that Microsoft sacrificed battery life for svelteness, with the Pro 4 measuring 0.03 inches thinner and weighing 0.07 pounds lighter (for the Core m3 version) compared to last year’s model.
Although Microsoft advertises the same 9 hours of video playback in both versions, the Surface Pro 4 lasted for 8 hours and 1 minute in PCWorld’s benchmarks for normal Office use. The Surface Pro 3 managed an extra 38 minutes in the same test. (As a Surface Pro 3 owner, I’d say it’s not uncommon for the i5 version to last just six hours on a charge.) Keep in mind that PCWorld’s testing was for the Core i5 model of the Surface Pro 4; we haven’t yet tested the Core m3 version to see if battery life is any better.
Thermal issues aside, iFixit noted that the Surface Pro 4 is just slightly easier to repair than its predecessor, using less adhesive to hold everything together. It’s still a major hassle to crack open, but the solid state drive is replaceable with the right tools and some elbow grease.
Why this matters: Performance aside, Microsoft’s spec sheet for the Surface Pro 4 tries to mask some of the differences between models, advertising the same battery life across the board and not mentioning the lack of a fan in the m3 version. The entry-level model now seems a bit more compelling than it did before, especially if it ends up providing some tangible battery life benefits.