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I currently have a slow 5400 rpm drive in my laptop and I am looking at installing a 7200rpm drive.

The new drive is reported to be 100 times faster than the old drive. The traditional advice would say that a 7200rpm drive, drain laptop batteries faster, however if you compare the specifications this appears not to be the case is this correct? For example:

My current 5400rpm drive:

  • spin up power: 4.5w
  • seek power: 2.2w
  • read/write: 1.9w

Replacement 7200rpm drive:

  • seek power: 2.3w
  • read/write: 2.1w
  • spin up power: 5.5w

If I read this correctly, does this mean switching to a 7200rpm drive will have a negligible power drain impact? For those interested, I am comparing the following two drives:

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migrated from Dec 4 '10 at 22:33

This question came from our site for system and network administrators.

Note regarding which stackexchange site is best, this site seems to have hardware related stuff, ie… – Jacob Rhoden Dec 4 '10 at 22:05
Hardly 100 times faster, possibly 50% faster on a good day but probably closer to 25% on average. is where this belongs BTW. – Helvick Dec 4 '10 at 22:11
@Jacob - SF is "...for system administrators and IT professionals, people who manage or maintain computers in a professional capacity." (from the FAQ). Questions like yours are typically better handled over on SU. It'll get migrated there shortly, no need to re-post. – EEAA Dec 4 '10 at 22:14

I think you will find that those 'small' differences will have a significant impact on battery life. It's not going to halve it but it will be noticable.

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Anecdotally, I can say that when I moved from a 5400 RPM drive to a 7200 RPM drive in my old laptop, I did not notice any change in battery life, while I did notice an increase in performance. – nhinkle Dec 4 '10 at 22:41

Better materials will reduce the friction in the spindle once it has spun up, leading to lowered power use while spinning. Do note the difference in the spin-up power of the drives though; the drive that spins faster needs more power to get spun up.

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