HDD Platter Density

[bob4432]

so, what are current platter densities? looking for a 1TB, either 2.5 or 3.5" 5400-7200 rpm for data storage. will be running raid1 - platter density is what i want. looking for a good drive, cool running that hasn't had many issue but again, want the highest platter density. this array will hold backups of other machines and then also some video/audio, along w/ be the drives for an ftp server i run from home.

thx for the info

 

[Soulkeeper]

most current drives are at 500GB/platter (up from 320GB/p for last gen) with rumours of 640GB/platter or possibly 750 coming sometime around november.
Laptop drives are slightly different

 

[jimhsu]

There appears to be some sort of fundamental bottleneck right now that won't go away unless we adopt something like this: http://www.nature.com/nphoton/journal/vaop/ncurrent/abs/nphoton.2010.90.html. Apparently the paper gives a roadmap to achieve 10 terabits/in^2 with minimal difficulty.

 

[Emulex]

3tb and 4tb drives will be rolling along soon - probably more platters. 600gb 2.5" sas too 🙂 good times

 

[jimhsu]

3tb and 4tb drives will be rolling along soon - probably more platters. 600gb 2.5" sas too 🙂 good times

Right, more platters is certainly a possibility. But areal density is pretty much bottlenecked at this point in time.

Source: http://www.theregister.co.uk/2009/11/10/bpm_or_hamr/

The technique in the nature paper is to basically heat up microscopic portions of the platter to make it easier to change the magnetic state. Specifically, they incorporate both Heat-assisted magnetic recoding (HAMR) and discrete track recording (DTR) together, which somehow complements the flaws in both approaches. Unfortunately I have no further idea how plasmonics works -- it's been a while since my QM classes.

 

[Soulkeeper]

Right, more platters is certainly a possibility. But areal density is pretty much bottlenecked at this point in time.

Source: http://www.theregister.co.uk/2009/11/10/bpm_or_hamr/

The technique in the nature paper is to basically heat up microscopic portions of the platter to make it easier to change the magnetic state. Specifically, they incorporate both Heat-assisted magnetic recoding (HAMR) and discrete track recording (DTR) together, which somehow complements the flaws in both approaches. Unfortunately I have no further idea how plasmonics works -- it's been a while since my QM classes.

There was a recent article for this on arstechnica today

 

[bob4432]

500GB platters would be just fine, didn't know they were near that high, last time i looked it was the 320GB platters and i thought that was amazing. would these just be the latest gen of drives that have these? how long have they been out and has there been any issues due to the density?

sorry, no sas conroller but appreciate the offer, was looking to see if the laptops had a higher platter density or if they just added more platters.

 

[Emulex]

yeah 1TB 2.5" drives are extremely thick still. usually too thick unless you are removing the dvd-burner and using that space. even then its usually not enough space.

laptops - too fragile imo - keep to ssd. should see intel 320gb mlc for 160gb pricing by end of year. thats decent.

 

[jimhsu]

There was a recent article for this on arstechnica today

Yea, that was the one I was looking for.

With a middle prong of 20-25 nanometers and each track separated by 24 nanometers, researchers found they could write to areas as small as 15 nanometers in diameter without affecting surrounding data. The efficiency of the signal from waveguide to antenna was about 40 percent, though the overall error rate was low and the system could write at speeds of 250 megabits per second. Researchers were easily able to obtain a density of one terabit per square inch, and posit that densities of 10 terabits per square inch are theoretically possible using this method.

On anandtech right now, there is news of a 3 TB drive. Personally I think its more likely that they stuffed more platters, but it's possible that they made some incremental improvements to density.

 

[Zap]

would these just be the latest gen of drives that have these? how long have they been out and has there been any issues due to the density?

Yes, latest generation. Funny you should mention issues due to density. Seems like most of the higher capacity drives suffer from higher failure rates, judging from Newegg reviews. Of course that could be issues totally unrelated to density, such as WD and Seagate firmware issues, or Newegg packaging issues.

On anandtech right now, there is news of a 3 TB drive. Personally I think its more likely that they stuffed more platters, but it's possible that they made some incremental improvements to density.

I think it is an areal density improvement because all the HDD manufacturers have traditionally maxed out at particular number of platters. For instance, WD and Seagate max out at 4 platters, Hitachi at 5 and Samsung at 3... though Samsung may have moved up to 4 with their latest 2TB drive.

I think 5 platters is the most that could physically fit in a 1" tall drive.