2nd HDD in T400s - Power Usage

I know a lot of you have been swapping out the optical drive for a 2nd hard drive ultrabay adapter on the T400s. It seems that a typical 2.5" HDD uses an average of 2-3W of power when active. This seems like a significant amount when compared to the 8W idle usage for the T400s.

Does anyone have any numbers of the battery life when using a 2nd HDD in the T400s? On a related note, any recommendations for a low power 2.5" traditional HDD?

 

2-3W when active is probably about right. However, you need to realize that this is likely less power than your optical drive uses. Additionally, when powered down the additional hard drive should use less than 0.5 watts.

In general I would recommend a 5400 RPM 2.5" drive. A single platter model (e.g. 160GB from a 320GB line, or 250GB from a 500GB line) is often slightly cooler, quieter, and more efficient. I have heard particularly good things about Hitachi 2.5" drives for energy efficiency at both idle and sequential reads (e.g. playing back a video file).

 

I was thinking about this as well, though I'll point out that the power manager is also capable of powering down the optical drive to use less power as well.

Out of curiosity, why do you recommend the 5400 RPM drive over the 7200 one? Sure, it will use less power when active, but will have to be active for longer to get the data.

 

another option is getting a SSD. the newest samsung have the lowest power usage of most SSDs and have great value for their performance. Corsair also sells rebranded samsung ssds. The model for the Corsair is P128 for the 128gb and P256 for the 256gb.

 

Sure, but that defeats the purpose of having a SSD+HDD combination setup (the main drive of the T400s is only 1.8", so you can get a faster SSD, and then put a bigger capacity drive in the optical bay).

 

Fantastic question. I've been thinking about doing this as well and going the SSD route, but their still so damn expensive. From a cost>performance ratio I think a 5400RPM drive would make more sense, seeing that you would only really benefit from the SSD if the OS were installed on it.

 

Suggest put HDD in spindown mode when not in use using hdparm-for-windows. Can also hotswap in/out the optical drive using hotswap! software. See sig on optical bay caddy usage to get the most mileage from this sort of setup.

 

I agree with jonlumpkin, I have a single platter 250GB HDD from Hitachi (5K500.B-250), and is totally silent, IIRC this is the second drive that uses the least amount of power according to Toms Hardware, the other one is the newer model from Toshiba's. I prefer Hitachi, I've set the drive parameters to spin down when not using it via Hitachi Feature Tool, actually I can hear the platters spinning down when not using it, so I think this model or the full 500GB models are fine drives to use, and very fast too max read speed is about 81MB/s.

 

Well, that really depends on what you're doing. If you are running a VM or transferring A Lot of Large files between the SSD and HDD then it may make sense to get a 7200 RPM.

However, if you primarily use the HDD as a repository for music, videos, ISOs, pictures and other large files you will rarely find that the 5400 RPM drive is taxed. Additionally, a 5400 RPM drive will use less power for a long constant read (e.g. playing music/video) than a 7200 RPM drive.

 

Great explanation, thanks. So, in general, 7200 is better for apps/system(/swap), etc. and 5400 is more useful for data. I figure moving around large chunks of data is (hopefully) a rare activity, so that aspect of the long constant use isn't as bad. How would the 5400 vs 7200 be for games? Clearly not going to do that on a T400s, but just curious.

 

It depends on what time in the cycle you are.

At some points the newer 7200rpm are more energy efficient then any of the previous discs while also being faster.

And at some point in the cycle the 5400rpm discs are just as fast as their 7200rpm counterparts, while being just as fast and bigger.

 

Wait, what? Aren't the 7200 RPM drives always be faster than the 5400 ones, by definition?

Which do you recommend, then?

 

Got WD Scorpio Black 7200rpm 320GB in my ultra-bay iii adapter - super quiet and also fast Of course not as fast as my SSD system drive, but good enough for data storage. Just as a comparison, in my previous T60 I had 200GB (7200rpm, Hitachi) and run a number of music application with multi-gig sound sample libraries. Now, I have all my programs/applications on SSD drive while the same sample library is on WD Scorpio in ultra-bay. I can see it running smoother with less lag than in my previous T60 setup. BTW, Scorpio Black is under $80, dirt cheat and very highly rated. Just my 2 cents

 

No, not per definition.

It also depends on the density of the used platters.

The 7200rpm discs often lag behind the 5400rpm ones when it comes to data density. That means that there are less bits to read during one rotation, and therefor 5400rpm discs can be as fast as 7200rpm discs when it comes to transfer rate.

However, on accestime the 5400 discs always loose. After the head has repositioned itself above the requested track it takes half of the rotation time (on average) before the right sector is under the head to start reading / writing. With 7200 rpm discs that is (1/7200) = 8.33 ms
For 5400rpm discs that is (1/5400) = 11.11 ms

The total accestime if offcourse the above given numbers PLUS the time that the head needs to move.

The platter density has some variables:

-Tracks per sector
-Bits per track

An increase in the number of tracks per sector increases the drives capacity. The tracks become smaller and therefore more data fits on a equal sized platter.

An increase in the amount of Bits per track also increases the capacity, but also increases the number of bits that pass the head during one rotation. Therefore, this means also on increase in the transfer rate.

Now let's compare two drives:
WD3200BEKT (320GB, 7200rpm, 2 platters of 160GB)
WD5000BEVT (500GB, 5400rpm, 2 platters of 250GB)

The WD3200BEKT gives HD-Tune results as 62MB/s average read and 15.2ms accestime
This screenshot is from this drive in my ThinkPad T61 7664-16U (with one GB RAM added):


The WD5000BEVT gives these results: 62 MB/s average read and 16.8ms accestime.
This screenshot comes from another T61 user:

Source:
http://forum.notebookreview.com/showthread.php?t=350375
(Great topic on this issue btw)

Had the 5400 had the same 160GB platters as the WD3200BEKT, the transfer rate would be (5400/7200)*62MB/s = 46.5 MB/s
So in order to maintain the transfer rate at 62 MB/s, they had to increase the number of bits per track with 33%. That would result in a platter of 213GB versus 160. So the last 37GB of capacity increase is in the increase in the number of tracks per sector.

So we see here two things:
The WD5000BEVT has the same transferrate because of the higher data density.
The WD3200BEKT wins on the accestime, thanks to it's higher rotation speed.

That being said you need to review more aspects to make a good choice. Like noise, energy consumption, vibration, what the drive will be used for and price.

Now you would think that 7200rpm drives would use more energy. That is true... but only when comparing to 5400rpm drives that use the same technology. 7200rpm drives in the notebook branche are often a show-off product. They use the new energy-saving technologies first in their 7200rpm line-up. When the WD3200BEKT hit the market for example, it's generation of 7200rpm HDD's was more energy efficient then any 5400rpm competitor from the past. I didn't really keep up with the HDD news, but I suspect that the WD5000BEVT also uses the newer technology so it will use even less then the WD3200BEKT.

When I bought my WD3200BEKT it wasn't hard to make a choice: it was faster and used less energy then any previous serie HDD. It costed a little more.. but what the heck.



What I would recommend? Well, if I had to pick a drive for my operating system I would want something that has a low accestime. So that would be the WD3200BEKT (only checked the WD camp). Even if some 5400rpm disc would offer 75MB/s transferrate, I would still choose the 7200rpm disc for it's lower accestime.

Now let's say I have a fast disc for my operating system (that WD3200BEKT or even an SSD) and I want more storage for movies, photos, backups and other large documents. Well, that's easy: accestime is no concern here, so I probably pick something like the WD5000BEVT: low energy use, large capacity, low price per GB and transfer rate just as good.

Gaming doesn't depend at all on the harddrive, except when loading a map or when you have a shortage of RAM.

If you have a shortage of RAM: upgrade that. The choice between a HDD as RAM substitute is debating whether you get something 1000 times slower or 'just' 800 times slower.

If you want it to load the new level quickly: the 7200rpm discs. Often the games load many, many small files, so accestime is a concern here. Heck, even a 30MB/s SSD with 0.1 ms accestime is here often faster then a 60MB/s drive with 13 ms accestime.

If you have a T400s with a fast SSD as main drive (well, you can't have a T400s with a fast main drive that is not an SSD -because 1.8" HDD's are slow per definition-) and just want more storage you can either put down a huge chunk of rapidly devaluating dollars to buy an even faster devaluating high-capacity SSD OR you buy a high-capacity 5400rpm 2.5" HDD for a fraction of the price.

Inactive HDD's without OS on them can be put to sleep, saving the battery.

If it was me and I had a T400s with SSD and wanted more storage: I'd pick the WD5000BEVT over the WD3200BEKT. That is.. at first sight.

 

Whoops. I misread that faster as "faster spinning" instead of "faster transfer" which makes much more sense. But the explanation was excellent, and is greatly appreciated. Thank you muchly.

Am I right in thinking, then that the newest 500GB drives, like this one:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822148374 are then the best of both worlds - the higher density like the 500GB WD, but the faster speeds of the 7200 RPM drive, and so it would end up being better than either of alternatives? I don't know how this particular drive fares in terms of transfer speeds and power consumption, but it doesn't cost that much more than the others.

I agree completely on the SSD. I'd would never pay the 600-800(+?!) for a 256GB one when prices are changing so rapidly. The only reason I'm even considering the larger Intel drive is because the T400s has the small 1.8" drive slot, and it seems much harder to find drives that size. I'd hate to buy something only to have the standard change again (1.8" long-side full-SATA, anyone?) and then not be able to get something better easily, or without great expense. On the other hand, with netbooks gaining popularity, maybe the 1.8" drive will become even more common.

One last question for you: you say "If it was me and I had a T400s with SSD and wanted more storage: I'd pick the WD5000BEVT over the WD3200BEKT. That is.. at first sight." - what do you mean? Under what conditions would you choose the 7200 RPM one?

Thanks again.

 

If you are considering the 500GB 5400rpm WD Scorpio Blue, you might prefer the new 640GB WD Scorpio Blue. It has 2 X 320GB 5400rpm HDD's rather than the 2 X 250GB 5400rpm HDD's of the 500GB. Look for the specs of each platter, not the total of the platters added up.

 

Yes, the Seagate you linked to has indeed a higher transferrate compared to the WD3200BEKT and WD5000BEVT due to it simply spinning 33% faster compared tot he WD5000BEVT. This also translates into transfer rates just above 80 MB/s (7200/5400)*62=83 MB/s

I wouldn't just pick that drive because of those specs. Seagate has a mixed record on noise and energy consumption, especially in their desktop drives. (Seagate 7200.10 vibrating room-heaters anyone?)

I would choose the 7200rpm if the WD5000BEVT would use 50% more energy for example. Or if it produced two times the noise. Or if it would vibrate a lot more. Or if the failure rate was four times higher.
Those parameters aren't given in any webshop unfortunately. The real-life shop on the corner sells 99% of the time BS on these parameters or simply doesn't know, so you need to read some online reviews from sites that actually tested the drive (or from guys here or on thinkpads.com). NOT from 'user reviews' on sites like newegg. That only gives a lot of crap. Or if you have a guy in the family that keeps up to date on this; ask them. With the remark that most people also sell bs to their families. I don't want to count how many times I had to fix something ridiculous that was recommended to these people "by our nephew" / "a good friend". At some point I had to fix the wireless settings on the laptop of an elder couple. The connection was flipping from 54Mbit/s to 14 Mb/s to no connection at all while being only 5 meters away from the accespoint. I asked them why they bought that particular model of accespoint. The answer was simple: "A good friend of us recommended us this particular model" Well, it was a $30 piece of Sweex (a brand that sells crappy stuff in my country)

Hmm, a little offtopic

It's a pleasure

 

Thanks a lot for the comparison! It was extremely informative. I ended up purchasing a Seagate 5400.6 320gb over a 500gb because it was a weekly sale item One downside of using the HDD adapter that I didn't foresee is that even with a quite conventional hard drive, nothing compares with the pure silence of the built-in SSD.