Apple's MacBook Pro with 128GB SSD: Performance and Battery Life Investigated

Better Battery Life? Not Necessarily

Hitachi lists the read/write power of the 5K250 that comes in the MacBook Pro as 1.7W on average. Idle power is even lower obviously. Memoright doesn’t provide similar specs on the MR25.2-128S but the top of the drive already tells an interesting story: 600mA at 5V, or 3W. It looks like in the quest for greater performance, the Memoright drive actually consumes more power than a mechanical disk drive. While Flash memory should have no problems running at 3.3V, I suspect that the FPGA and PATA-SATA bridge both require a 5V input which is why the drive uses 5V power from the SATA power connector and not 3.3V.

With potentially greater power usage, it doesn’t look like we’ll be gaining any battery life from the SSD. To confirm, we ran the same battery life tests we have been using in our recent MacBook Air and MacBook Pro reviews:

The wireless browsing test shows the mechanical disk offers a slight battery life advantage of around 8 minutes over the SSD system. While losing 8 minutes of battery life isn’t tremendous, the point is that battery life doesn’t improve any.

The DVD playback test paints the SSD’s battery life in the worst light; the system equipped with a mechanical disk outlasts it by around 8%. In the case of the MacBook Pro, that 8% translates into 18 minutes of battery life.

Our final test shows no difference between the mechanical and SSD drive.

It’s worth noting that how the SSD fares really depends on the reference point. Had we used an older, higher power mechanical disk the situation might have been different. A quick look at the specs for the 7200RPM drive that Apple offers on its MacBook Pro shows that despite a faster spindle speed, power consumption would increase to 2.3W, still lower than the Memoright drive.

Memoright doesn't list more detailed power specs for its drive so it's possible that the difference is closer, but without a doubt the SSD doesn't offer any power advantages in this case. The battery life tests provide an important distinction, as we saw battery life increase in the MacBook Air but decrease here. It just goes to show you that simply switching to a SSD won't necessarily improve battery life, it depends on what you're switching from and what you're switching to.