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shiato storm

macrumors member
Original poster
Jun 7, 2007
95
0
Bristol UK
I was trying to find some power usage comparisons between the 320gb 7200rpm and 500gb 5400rpm HDD's (for notebooks). I installed a 320gb into my mbp (15" mid 08 model) - with the standard 160gb as back up - I have my concerns about power consumption and was considering moving to a 5400rpm drive to compensate. Is a 500gb 5400rpm drive about the same in this respect, therefore would I have to go to a 320gb 5400rpm drive to notice a difference? [increased battery life...]
 
A 7200RPM drive will give you a longer battery life than a 5400RPM drive.

I know you wouldnt think it would be like that, but it is, theres loads of threads on it already here, so im not going to spend time searching out articles, but if your really desperate I will explain why.
 
A 7200RPM drive will give you a longer battery life than a 5400RPM drive.

I know you wouldnt think it would be like that, but it is, theres loads of threads on it already here, so im not going to spend time searching out articles, but if your really desperate I will explain why.

What is your explanation?
 
2 reasons

1) With a 5400rpm drive your computer will take longer to boot, costing you a few minuets battery life

2) A 7200RPM drive whilst spinning faster can acess data quicker, and therefore has to spend less time spinning, so saves power.
 
2 reasons

1) With a 5400rpm drive your computer will take longer to boot, costing you a few minuets battery life

2) A 7200RPM drive whilst spinning faster can acess data quicker, and therefore has to spend less time spinning, so saves power.

Everything I've read points to the battery life being less with a 7200 rpm drive. The difference is somewhat negligible, however, at only a decrease of 5-10 minutes.

While this is old, it's still relevant: http://barefeats.com/hard56.html

What is your source?

I'm giving this a bump back up. I'm interested in this since I'm looking at the upcoming 7200rpm 500gb drive.
 
I too would be interested in specifics. However, it strikes me from everything I've read that the difference, either way, is insignificant when measured against the benefits.
 
I recently switched from a 5400 to 7200 rpm drive and didn't notice any difference in real-world usage. I did however see a faster overall responsiveness (though it may just be the snappy-safari effect). Additionally, if noise is a factor, a 7200 rpm drive may be louder.
 
so its still an open verdict really then. data I've seen doesn't seem comparable due to differences in set ups

Yeah, the consensus seems to be (along with my own experience) that the battery life difference is negligible.

kastenbrust seems to like making things up for the sake of appearing intelligent (based on his other threads). I was pretty sure he was doing the same thing here.
 
kastenbrust seems to like making things up for the sake of appearing intelligent (based on his other threads). I was pretty sure he was doing the same thing here.

Actually the reasons he posted are true, but the battery life increase might be 10 minutes or it might be 2 minutes. You would have to be hitting the drive constantly for any real decrease in battery life. In my mind, the benefits FAR outweigh the penalties.
 
Yeah, the consensus seems to be (along with my own experience) that the battery life difference is negligible.

kastenbrust seems to like making things up for the sake of appearing intelligent (based on his other threads). I was pretty sure he was doing the same thing here.

Anyone who knows even a little about Hard drive hardware will understand what I wrote is true, dont whine just because some people know more than you about computers. I probably do appear intelligent given I have a masters in computer engineering, however if I offended your ego thats not the way I mean to come accross.

However here are some sources for more information for the Original Poster:

http://www.barefeats.com/hard80.html

http://www.tomshardware.com/reviews/fast-furious,1169.html

"On the other hand, as you see above, the power usage penalty is about 10% for choosing a 7200rpm drive over a 5400rpm drive while the latency advantage is 31%. Therefore, it could be argued that the lower latency and faster seek time means the 7200rpm drive spends less time working -- thereby conserving power usage."

Barefeats is quite good for random and hard to find benchmark comparisons, if you search around you'll find lots of comparisons proving my point.
 
Anyone who knows even a little about Hard drive hardware will understand what I wrote is true, dont whine just because some people know more than you about computers. I probably do appear intelligent given I have a masters in computer engineering, however if I offended your ego thats not the way I mean to come accross.

However here are some sources for more information for the Original Poster:

http://www.barefeats.com/hard80.html

http://www.tomshardware.com/reviews/fast-furious,1169.html

"On the other hand, as you see above, the power usage penalty is about 10% for choosing a 7200rpm drive over a 5400rpm drive while the latency advantage is 31%. Therefore, it could be argued that the lower latency and faster seek time means the 7200rpm drive spends less time working -- thereby conserving power usage."

Barefeats is quite good for random and hard to find benchmark comparisons, if you search around you'll find lots of comparisons proving my point.

That's well and good. But in Normal usage if you are constantly accessing the drive and that drive uses more energy then a standard 5400 rpm drive then it will indeed use more power. If you boot your computer up and idle then you will see a negligible power savings.
 
That's well and good. But in Normal usage if you are constantly accessing the drive and that drive uses more energy then a standard 5400 rpm drive then it will indeed use more power. If you boot your computer up and idle then you will see a negligible power savings.

Oh yeah theres a point there too, most modern 7200rpm drives are more power efficient due to better design than 5400rpm drives, not always, but usually.
 
Oh yeah theres a point there too, most modern 7200rpm drives are more power efficient due to better design than 5400rpm drives, not always, but usually.


If you look are most power ratings for Laptop Hard Drives. The 7200 RPM drives consume a watt or more, more power as compared to their 5400 RPM siblings. Yea when they do spin up they access data faster. But it depends on how you use the drive.

What the 7200 RPM drive gives you is a faster performing system, so you can get more done then a 5400RPM drive. And because of this the battery life gains or losses are negligible.
 
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