7 ms·

Can someone explain to my why SSDs still cost more than HDDs? When I look at all the moving parts in an HDD, I'm shocked they can still be produced for less.

Joeri 11y ago
You need to look at the amount of moving parts in the factory, not in the product.
- teekert 11y ago
  Exactly, I just went to a talk by someone from ASML, a modern processor may go through 700 sequential steps of (UV) illumination, "sanding" (to moleclar flatness) and adding a new layer of lithographic material. It's insane and there are hardly any working specimens in the first batches.
  - andrepd 11y ago
    >there are hardly any working specimens in the first batches Why is that?
    - mozumder 11y ago
      Way too many atoms in the wrong places. Building a transistor on a chip is like making a building by bombarding meteors from space and hoping the craters form the shapes you want. Building a chip is like making a city with that process.
      - jsprogrammer 11y ago
        I think the post was was asking why the first batches are special in that regard (atoms in the wrong places) as opposed to the (presumably successful) later batches.
        rasz_pl 11y ago
        process tuning
    - sliverstorm 11y ago
      It's ultraviolet voodoo, and every successive generation is tackling new problems of minuteness that have never been dealt with before. When was the last time your first program in a language you've never used before compiled & ran on the first try?
      - MaysonL 11y ago
        Back in 1963, and it was my first dozen programs, one a week for 12 weeks. The 13th week, I wrote my first assembly language program, and it had a comma where it should have had a period (or was it the other way around?:-) ). I never did get that program working, because that was the week NASA sent up a new weather satellite, and there was no more computer time to waste on high school students and their trivial programs.
pen2l 11y ago
HDDs cost more because they consist of technologies understood and implemented in factories for long. Manufacturing of SSDs is different, and it'll take some time for manufacturing companies to get up to speed, at least to overtake the scaled assembly line operations of HDD manufacturing. My bet is by the end of next year, SDDs will be cheaper than their equally sized HDDs. HDDs are certainly on their way out.
- wmf 11y ago
  SSDs are just chips on boards, which are manufactured using very mature, very high volume technology and yet they improve at best 2x/year. There is no reason why SSD prices would drop 10x in one year. Hetzler et al. have calculated that the industry would have to spent over $800B to build enough fabs to replace hard disks with SSDs. http://storageconference.us/2013/Papers/2013.Paper.01.pdf http://storageconference.us/2013/Papers/2013.Paper.01.pdf
  - mcshicks 11y ago
    I think the big story here is the number of chips they can stack. From the article you pointed out to they were using 8 stacked dies. "The later capacity is accomplished using 8 stacked and thinned (< 75 um) NAND chips in a 1.2 mm package" The samsung one has 48 layers per the article. So that's a 6x improvement.
    - wmf 11y ago
      You're kind of mixing up a few things. 3D NAND (aka V-NAND) has many (48) layers per die, and then they also stack those dies. But they made each cell much larger, so going from 1 layer to 48 layers is only a net density increase of 2x.
      - mcshicks 11y ago
        You are absolutely correct. Thanks.
com2kid 11y ago
A large piece of spinning rust and some mechanics are cheaper to produce then billions of NAND cells. Humans are pretty damn good at making small precise mechanical movements.
- hga 11y ago
  And it's a more mature arena; mechanical watchers are I'm sure a better example (Gerry Sussman likes to tinker with them to relax, or at least did that while doing his Ph.D. thesis to stay (semi-)sane), but in the area I know best, everything came together for high power rifles in the 1898 Mauser (although reliably getting the steel right took longer world-wide for the first world). Or look at internal combustion engines. The two absolutely critical technology improvements that changed things from WWI to WWII were "merely" refinements in those and radios. WWI IC engines were so rough they pretty much required wooden frames, and engine power was anemic, as WWI tanks show. Fast forward not very many years and we have much smoother and reliable powerful engines, and had developed the seeds of today's jet engines before the first transistor was demonstrated in 1947.
mozumder 11y ago
You're paying for $5 billion in lithography steppers and other fab equipment for one factory (you'll LOL at the cost of 1 deep-UV immersion litho stepper). That's amortized over 5 years. There's also masks, and process research costs, in addition to the basic materials costs. Did you know that a silicon wafer is a perfect crystal, structured like a diamond? Silicon is right underneath Carbon in the periodic table, which means it shares the same outer electron shell configuration. Making that ain't cheap. And if one atom is in the wrong place, you have to throw away the chip. That kind of core expense doesn't exist in a hard drive factory. The disks in a hard drive don't have to be perfect crystals, for example. It's a LOT more expensive to produce chips. Multiply all the distribution and sales costs, and you'll understand why it's so expensive.
- maxhou 11y ago
  > And if one atom is in the wrong place, you have to throw away the chip this is certainly the case for CPU but DRAM & NAND ? this is the typical case of designs where you can add redundancy to accomodate for manufacturing defects.
  - mozumder 11y ago
    At the cost of increased die-size. If it helps any just think of the costs as buying diamonds. "Wow that's 16TB of diamonds!" or: "this GPU uses a bigger diamond than that GPU"
    - hbosch 11y ago
      It doesn't exactly help your cause that many people also believe the cost of diamonds is artificially inflated as well.
      - kedean 11y ago
        The cost of diamonds IS artificially inflated. They are useful for purposes other than the one in which the price inflation is a big deal, but it is a demonstrable fact that the price is inflated.
sliverstorm 11y ago
It's not always intuitive! Another incredible one- the silicon industry absolutely bends over backwards to keep using silicon and UV, instead of GaAs, E-UV, and other exotic processes. As much as silicon & UV can be a colossal billion-dollar pain in the butt, it's still easier & cheaper than E-UV. Or automotive engines. We have all sorts of technology tacked on around the basic ICE gasoline engine to make them better- the combustion chamber is just a tiny piece of the machine, which is tended by countless devices managing temperature, airflow, fuel flow, air velocity, etc. Tremendously complex compared to electric motors- but in the end, they are still more popular than electric motors because of the fundamental problem of batteries.

Joeri 11y ago

You need to look at the amount of moving parts in the factory, not in the product.

teekert 11y ago
Exactly, I just went to a talk by someone from ASML, a modern processor may go through 700 sequential steps of (UV) illumination, "sanding" (to moleclar flatness) and adding a new layer of lithographic material. It's insane and there are hardly any working specimens in the first batches.
- andrepd 11y ago
  >there are hardly any working specimens in the first batches Why is that?
  - mozumder 11y ago
    Way too many atoms in the wrong places. Building a transistor on a chip is like making a building by bombarding meteors from space and hoping the craters form the shapes you want. Building a chip is like making a city with that process.
    - jsprogrammer 11y ago
      I think the post was was asking why the first batches are special in that regard (atoms in the wrong places) as opposed to the (presumably successful) later batches.
      - rasz_pl 11y ago
        process tuning
  - sliverstorm 11y ago
    It's ultraviolet voodoo, and every successive generation is tackling new problems of minuteness that have never been dealt with before. When was the last time your first program in a language you've never used before compiled & ran on the first try?
    - MaysonL 11y ago
      Back in 1963, and it was my first dozen programs, one a week for 12 weeks. The 13th week, I wrote my first assembly language program, and it had a comma where it should have had a period (or was it the other way around?:-) ). I never did get that program working, because that was the week NASA sent up a new weather satellite, and there was no more computer time to waste on high school students and their trivial programs.

pen2l 11y ago

HDDs cost more because they consist of technologies understood and implemented in factories for long. Manufacturing of SSDs is different, and it'll take some time for manufacturing companies to get up to speed, at least to overtake the scaled assembly line operations of HDD manufacturing. My bet is by the end of next year, SDDs will be cheaper than their equally sized HDDs. HDDs are certainly on their way out.

wmf 11y ago
SSDs are just chips on boards, which are manufactured using very mature, very high volume technology and yet they improve at best 2x/year. There is no reason why SSD prices would drop 10x in one year. Hetzler et al. have calculated that the industry would have to spent over $800B to build enough fabs to replace hard disks with SSDs. http://storageconference.us/2013/Papers/2013.Paper.01.pdf http://storageconference.us/2013/Papers/2013.Paper.01.pdf
- mcshicks 11y ago
  I think the big story here is the number of chips they can stack. From the article you pointed out to they were using 8 stacked dies. "The later capacity is accomplished using 8 stacked and thinned (< 75 um) NAND chips in a 1.2 mm package" The samsung one has 48 layers per the article. So that's a 6x improvement.
  - wmf 11y ago
    You're kind of mixing up a few things. 3D NAND (aka V-NAND) has many (48) layers per die, and then they also stack those dies. But they made each cell much larger, so going from 1 layer to 48 layers is only a net density increase of 2x.
    - mcshicks 11y ago
      You are absolutely correct. Thanks.

com2kid 11y ago

A large piece of spinning rust and some mechanics are cheaper to produce then billions of NAND cells. Humans are pretty damn good at making small precise mechanical movements.

hga 11y ago
And it's a more mature arena; mechanical watchers are I'm sure a better example (Gerry Sussman likes to tinker with them to relax, or at least did that while doing his Ph.D. thesis to stay (semi-)sane), but in the area I know best, everything came together for high power rifles in the 1898 Mauser (although reliably getting the steel right took longer world-wide for the first world). Or look at internal combustion engines. The two absolutely critical technology improvements that changed things from WWI to WWII were "merely" refinements in those and radios. WWI IC engines were so rough they pretty much required wooden frames, and engine power was anemic, as WWI tanks show. Fast forward not very many years and we have much smoother and reliable powerful engines, and had developed the seeds of today's jet engines before the first transistor was demonstrated in 1947.

mozumder 11y ago

You're paying for $5 billion in lithography steppers and other fab equipment for one factory (you'll LOL at the cost of 1 deep-UV immersion litho stepper). That's amortized over 5 years. There's also masks, and process research costs, in addition to the basic materials costs. Did you know that a silicon wafer is a perfect crystal, structured like a diamond? Silicon is right underneath Carbon in the periodic table, which means it shares the same outer electron shell configuration. Making that ain't cheap. And if one atom is in the wrong place, you have to throw away the chip. That kind of core expense doesn't exist in a hard drive factory. The disks in a hard drive don't have to be perfect crystals, for example. It's a LOT more expensive to produce chips. Multiply all the distribution and sales costs, and you'll understand why it's so expensive.

maxhou 11y ago
> And if one atom is in the wrong place, you have to throw away the chip this is certainly the case for CPU but DRAM & NAND ? this is the typical case of designs where you can add redundancy to accomodate for manufacturing defects.
- mozumder 11y ago
  At the cost of increased die-size. If it helps any just think of the costs as buying diamonds. "Wow that's 16TB of diamonds!" or: "this GPU uses a bigger diamond than that GPU"
  - hbosch 11y ago
    It doesn't exactly help your cause that many people also believe the cost of diamonds is artificially inflated as well.
    - kedean 11y ago
      The cost of diamonds IS artificially inflated. They are useful for purposes other than the one in which the price inflation is a big deal, but it is a demonstrable fact that the price is inflated.

sliverstorm 11y ago

It's not always intuitive! Another incredible one- the silicon industry absolutely bends over backwards to keep using silicon and UV, instead of GaAs, E-UV, and other exotic processes. As much as silicon & UV can be a colossal billion-dollar pain in the butt, it's still easier & cheaper than E-UV. Or automotive engines. We have all sorts of technology tacked on around the basic ICE gasoline engine to make them better- the combustion chamber is just a tiny piece of the machine, which is tended by countless devices managing temperature, airflow, fuel flow, air velocity, etc. Tremendously complex compared to electric motors- but in the end, they are still more popular than electric motors because of the fundamental problem of batteries.