Much less power usage with the SSD
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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