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MikeyTree
Jan 31, 2008, 02:05 PM
Would having a SSD instead of a hard drive have an impact on the battery life of the MBA?



kyleen66
Jan 31, 2008, 02:07 PM
Would having a SSD instead of a hard drive have an impact on the battery life of the MBA?

Everything that I've heard is that they would make the battery last longer since there is no moving parts.

tersono
Jan 31, 2008, 02:07 PM
Yes, in theory the SSD should use less power than an HD. Whether it will be enough to be noticeable is questionable, though

Cybergypsy
Jan 31, 2008, 02:18 PM
nothing you would see 5%

aiongiant
Jan 31, 2008, 02:27 PM
compared to a 4200rpm drive
i say insignificant % hardly noticeable

nagromme
Jan 31, 2008, 03:08 PM
It would have some effect: spinning an HD up and down uses power, which is why an HD iPod gets lower battery life if you skip a lot. Not so with an SSD iPod.

But that little power savings isn't what I want, so much as the speed--and not having those little delays (seen even on desktop computers) when the HD spins up after sitting idle.

I also want the durability/longevity.

DaveC
Jan 31, 2008, 03:08 PM
According to this review from 8/07:
http://www.tomshardware.com/2007/08/13/flash_based_hard_drives_cometh/

For the 2.5" SSD vs HD, according to the manufacturer's specs:
SSD: 0W/1W/0.4W
HD: 5.5W/2.4W/0.6W
(Spin Up/Read+Write/Idle)

So for SSD vs HD, roughly 2.4x less usage while reading/writing, and 1.5x less while idle, with no power usage to "Spin Up" and no delay for a powered down drive (power saving mode) to spin up for use.

Interestingly enough, they also looked at SATA SSD's versus a PATA SSD (like the one Apple uses in the MBA) power usage when idle. The SATA consumes 0.4 W when idle, which is >10 times higher than the power consumption of the PATA, which consumes 0.05 W when idle. This could explain why Apple went with PATA despite SATA's improved performance. The hit on the battery life may not have been worth the added performance in their estimation.

What this translates to in real life use is something else completely. We'll have to see how the 64GB SSD holds up in real life use.

DaveC

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