SSD's actually decrease battery life?

recent article from tom's hardware:

http://www.tomshardware.com/reviews/ssd-hdd-battery,1955.html

i thought it was interesting. just something to think about before going with SSD. granted, performance is definitely better, but for the road warriors out there that need battery life over performance, you may want to think again.

hopefully, power saving features will soon be implemented in SSD's

 

It's an interesting read, we had a whole discussion on it in the Aftermarktet upgrades section (can't find it now).

In my opinion the truth is bit more complicated than what you write.

For example: the Macbook Air has proven that the SSD version does actually last longer on the battery than the HDD version. And in some benchmarks the HDD version outperforms the SSD version performance wise.

 

Amazing find. Thanks mate. I guess SSDs are still in the beta stage .

 

Read the user comments from the article. In the comments people discuss how the battery life test is flawed. The power consumption test results is what brings their battery life test in question.

In short, an SSD will complete tasks faster and sit idle longer than an HDD.

 

More, here: http://forum.notebookreview.com/showthread.php?t=208242&page=48

 

Well it's flawed in their opinion. In my opinion it's not flawed. And it seems like a lot of people are defending their choice for SSD.

But before we can make any conclusive remarks we need more testing.

 

When you test a drive sitting idle (i.e., the computer is doing nothing) to test for battery life you have two variables:

The independent variable - SSD/HDD idle load (watts)
The dependent vatriable - Battery Life

In this test, you can say with confidence that when SSD/HDD watts go up, battery life goes down.

TH introduces a second independent variable by using Mobilemark: the CPU. In some Mobilemark applications, CPU utilization may be higher and bottleneck the system moreso than the drive. In these situations, a fast drive would cause CPU intensive applications to run more often than a slower drive.

Had TH monitored CPU usage during the Mobilemark battery test, and found it to be equal across all tested drives, I would be more inclined to believe the battery life results.

Or better yet, they could just run another battery test using a single application looped over and over that would cause a consistent CPU utilization. Then you'd have the simple and conclusive independent/dependent test I mentioned above.

 

I understand the argument, I'm just not fully agreeing with it. Without getting into the details, I agree we ne need more testing.

The fact that some people are so involved in arguing in favor of SSD in the comments section is for me an indication that their beliefs are challenged.

 

It was certainly a thought provoking read, but I'm not sure it's correct. I agree with PhilFlow - more testing is required.

The gist of the criticism is logical - it's unfair to claim doing more work in less time is bad just because you're measuring battery life. Surely if you've done your days work in less time then you don't need the extra battery anyway... so the test doesn't seem fair. As the article's comments suggest, playing movies or similar would seem a fairer test. But just because their test rationale is questionable doesn't make it stupid - just that we need to look further into this before making a conclusion.

Another interesting point to investigate would be the power requirements during power-saving mode. On a traditional disk, I usually disable the 'turn off hard disks after x mins' option in Windows (especially on AC power) because it irritates me having to wait for some seconds for the disk to spin up again when I return to my computer. I'm guessing that SSDs don't suffer from the same delay..? Thus you could set the drives to power down after 1 min (or less if possible) on any power source without any noticeable penalty in responsiveness?
If this is the case, then SSDs would surely win in power saving because in 'turned off' mode they must consume less power than spindle-based HDDs in 'idle' mode. It's not a fair test in a way, because powered down HDDs would also use little power, but then power-down-to-powered-up transition for HDDs is an irritatingly slow process, so for me it would reflect how I would use the respective technologies.

All of the above assumes that there are effectively three states: off/powersave, idle (i.e. on but doing nothing) and busy (i.e. fetching or writing data). I'm assuming it's possible to 'switch off' a SSD drive in the same way traditional HDDs can be switched off after a set period of inactivity.

 

Yeah, Tom's doesn't mention all SSDs come with the laptops as factory default configuration. They just list aftermarket drives as an upgrade option for users to consider.
What I can see is MK1011GAH 100GB 1.8" has power consumption max 1.65W (3.3v 500mA).

Power Consumption:
Start: 1.8watts
Seeking: 1.1watts
Reading: 1.0watts
Writing: 1.0watts
Idle: 0.3watts
Standby: 0.12watts
Sleep: 0.07watts

But Samsung SSD modules only get 0.25W for reading and 0.36W for writing.
Samsung 32/64 GB SSD module link
Toshiba 100GB MK1011GAH HDD link

So it definitely save battery power, right?

 

No not necessarily. You can't go by factory specifications.

You need real life testing for conclusive results.

 

Definitely yes. Real life and factory specifications can't have a big difference.
Even the idle of hdd is about 0.3W is still higher than readiing state of SSD. It can't make any big difference in real life.

 

Lol. welcome to the computer industry.

 

Actually SSDs have been around for a very long time... the government, big companies, and the military have been using them for decades. People who actually own and use SSDs and have compared them with HDs have had an increase in battery life. Les, who probably has had more experience than the majority of us combined in SSDs also concurs with this sentiment and has commented about this in his SSD thread.

 

Don't lol too early. Someone will lol at you later.

 

Tx Sgogeta4,

The compliment is appreciated. You are absolutely correct when you suggest they get the true results from the horses mouth...

The controversy surrounding that article is very large.

 

I wasn't laughing at you, but at your statement.

But I'd love to see some benchmarks that show the real powerusage is actually as low as you state.

 

With my G, I'd say SSD life is equivalent to HDD. I knew from day 1 it wouldn't really affect battery life, but it has made the computer very usable (vs suffering with a 4200rpm drive). So it's all relative. I get anywhere from 6 - 9 hours of battery life depending on my usage.