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Hardware

Why Do Flash Drives Cost So Much? 45

Posted by Cliff from the lessons-in-hardware-economics dept.
Alvin Pettit asks: "I wanted to get a Flash drive for my PC for the following reasons: it is quiet, I can save electricity and I don't have to worry about moving parts. When I looked for these drives I found them to be rather expensive, much more so than the smaller devices such as CompactFlash! Why do Flash drives cost so much more than CompactFlash devices?"

"I looked up IDE flash drives compared to compact flash and this is what I found:

  • On pricegrabber:
    SanDisk Part# SD25B880402 880MB IDE 2.5 FLASHDRIVE is $1148.00
    This comes out to about $1.30 per meg
  • Where a compact flash is
    SanDisk Part# SDCFB1000768 1 GB COMPACTFLASH CARD is $589.00
    This comes out to about $.60 per meg
  • Even Ultra Compact flash is cheaper:
    SanDisk Part# SDCFH512784 512MB COMPACT FLASH ULTRA is $268.00
    This comes out to about $.52 per meg
Has anyone adapted compact flash drives to be used as bootable drives on PCs. I want to make a nice low powered quiet PC."
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Why Do Flash Drives Cost So Much? More

Why Do Flash Drives Cost So Much?

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  • Data rates (Score:2, Informative)

    by Drakon ( 414580 )
    a 1 gig flash card is limited by your USB speeds
    a 1 gig flash drive is limited by your system bus speeds

    the drives are MUCH faster
    • One thing to do to speed up Compact Flash is to get a Firewire CF drive [lexarmedia.com]. It will not bring it up to Flash drive speed, but the limiting speed will be the card, and not the interface.
    • Proof that being confident gets more karma than being right.

      Shut up your fool mouth, trollboy. WTF does flash have to do with USB?

      Whatever the reason it is cheaper, compact flash DOES have an IDE interface. For the price of a cheap converter cable, you could get the flash card and still save money while getting 100 more megs.

      If there is any truth in drakon's statement, it may be that the card is a bit slower, after all, some harddrives are faster than others. The flash drive may play a few tricks and buffer it to fast ram, or may even be 16bit data path, versus CF's oldschool 8bit data path. I'd still go with the card though.
    • a 1 gig flash card is limited by your USB speeds
      a 1 gig flash drive is limited by your system bus speeds

      the drives are MUCH faster

      1. What does this have to do with price?

      2. I have a PCMCIA card reader for my CF cards, where does USB speed fit into this equation? How much faster are the flash drives than my PCMCIA/CF card?

    • USB has nothing to do with CompactFlash...

      I have a CF->PCMCIA adapter - MUCH faster than a USB reader, and in fact indistinguishable from the much more expensive ATA PCMCIA cards.

      CF cards have a built-in IDE interface, connecting them to an IDE bus is a matter of passive wiring. (There are adapters to do this for $10-20, MAYBE $30, but I'm positive it's not more than that. My CF-PCMCIA adapter cost me $10)
  • ...it's probably for the same reason that Solid State memory costs more than regular DRAM.
    • ...it's probably for the same reason that Solid State memory costs more than regular DRAM.

      Um, what state is DRAM? Gas?
      • FYI, Solid State Memory and Flash memory are pretty much the same. Solid State RAM is a type of memory installed into certain machines. It is non-volitile (just so you know, silicon_synapse, that means when you turn the machine off, the data is stored, rather than disappearing). With sufficient space on the SSM, an individual can load one's whole OS into physical memory and have it stay. That generally leads to greater performance.

        Last time I checked, SSM was twice as much as comparable DRAM.


        BTW, I hope someone Meta-mods the off-topic marking for my on-topic proposed answer to the ORIGINAL "Ask Slashdot" question.
  • 1) Demand is much lower
    2) Parts count is much higher

    You can get a card reader for a desktop machine ($15-$80, depending on what you want) and just use compact flash cards. It just takes a lot of effort to boot from one. It is possible, though.

  • PC104 (Score:3, Interesting)

    by Oriumpor ( 446718 ) on Monday August 26, 2002 @07:16PM (#4144710) Homepage Journal
    From what I've seen , and what the guys at wearables [blu.org] it is indeed possible to construct a low power pc that boots off a PCMCIA (adapted CF) card.
    Although their end goals are not identical as yours, their immediate needs (low power) are the same.

  • Speaking of compact flash (Score:2, Interesting)

    by dozer ( 30790 )
    Why does nobody make one with a write-protect switch???

    They would be perfect for storing Tripwire databases, read-only boot partitions, etc. I've looked all over, though, and as far as I can tell, all of them are permanently read/write.
    • So modify the card.

      Most flash chips have a pin on them you can pull high to enforce write protect. All you should have to do is connect this up and you'll have a read-only card. Of course this may require some precision soldering as most flash chips are in very small formfactors...
  • Sensei Google says: DRAM is cheaper. [slashdot.org]
  • I beleive that Compact Flash cards are IDE compatable, all you need is to wire them up correctly.
    This google search should get some results [google.com]

  • Apples and Oranges. (Score:4, Informative)

    by WasterDave ( 20047 ) <[moc.pekdez] [ta] [pevad]> on Monday August 26, 2002 @07:59PM (#4144966)
    They're not the same thing, or at least they shouldn't be. Flash memory is *really* slow, fast random access, but spectacularly slow read/write. And it wears out. A good quality flash drive should be a stack of DRAM, a battery, and some way of backing up the DRAM when the power gets yanked (and vice versa). As you can imagine, this costs a bit and since it has low demand, it is also expensive.

    Dave
    • The wearing out part is overestimated usually. I know that this is a concern sometimes for people using handhelds to do odd things (you'd be amazed what you can do with Linux on an iPaq), and someone was concerned about wearing out their flash.

      Someone calculated that if you flash the flash in the iPaq as fast as possible, in a well distributed pattern (which CF cards do for you usually), it would take 12 YEARS to wear out a 32MB unit.

      12 years is an awful long time. In 12 years your wimpy 512MB-2GB flash drive will look like NOTHING (think about the old 120MB hard drives, I had one of those in my comp 12 years ago and now they're totally worthless).

      • Re:Apples and Oranges. (Score:1, Informative)

        by Anonymous Coward
        Flash is generally rated for one million write/erase cycles.

        It's well known (and easily proven) that running a standard linux distribution from flash will swiftly destroy the media due to the way the initial boot-time 'fsck' handles drive writes.

        • Hence why you use a journaling filesystem :)

          MTD devices (basically raw flash presented at the OS) usually end up with either CRAMFS (which is readonly) or jffs (usually v2) on it. JFFSv2 is journaling, and doesn't need to trash all over the place to fsck the drive.

          Of course, this could be a concern on CF cards since, when used in an adapter, they show up as normal IDE hard drives. Obviously, you'd want to use a journaling filesystem like ReiserFS, JFS, Ext3, XFS, or <instert journaling filesystem of the day here>.
        • The flash in my rio 300 wasn't good for a million writes. It was more like about 1000. Its 1st sector is broken so I have to take it apart and swap the chips around.
    • WasterDave writes:
      They're not the same thing, or at least they shouldn't be. Flash memory is *really* slow, fast random access, but spectacularly slow read/write. And it wears out. A good quality flash drive should be a stack of DRAM, a battery, and some way of backing up the DRAM when the power gets yanked (and vice versa). As you can imagine, this costs a bit and since it has low demand, it is also expensive.

      You're thinking of a RAM drive. These usually present a SCSI interface, and are really horrendously expensive. Often used to accelerate database performance on mid-range ($100K) solaris servers.

      There are a number of companies selling actual "flash" drives, both as CF-to-IDE harnesses and custom packaged in a laptop-drive form factor.

      These are nothing like RAM drives, and in fact are not really any more sophisticated than your standard "Compact Flash" storage card.

      Here's an example with some specs:
      http://www.acal.be/products/el/active/sandisk/sanc hip.htm [www.acal.be]

      I have a couple of 64Mb models, you can often find them on Ebay at reasonable prices. I use them to build Diskless FreeBSD [freebsd.org] hosts.

  • IDE to Compact Flash and More (Score:5, Informative)

    by MBCook ( 132727 ) <foobarsoft@foobarsoft.com> on Monday August 26, 2002 @08:05PM (#4144997) Homepage
    After a quick search on google, I found this link [pcengines.com]. It's an adaptor to let you attach a Compact Flash card to a standard IDE cable (they also have one for 2.5" IDE cables. From my understanding, this should appear as a perfectly normal hard drive to your PC, so you don't need anything odd to boot off it or use it in any other was (as opposed to what you'd have to go through to use a USB Compact Flash adaptor to boot from). This one is about $20, and I know there are others.

    Why do flash drives cost so much more? Most likely because they aren't easily found. They're not used much, and I'd assume that most of them have very fast access times (which is what you're paying the most for. Faster chips can be expensive as hell, but I bet there is nothing like being able to saturate your IDE channel with just one drive that you can't even hear). Of course this doesn't make a ton of sense, because to put a gig in a little CF card, the chips have to be incredibly small and dense. To put a gig of memory into something the size of a hard drive wouldn't need very dense or small chips (relitivly) and they could use more chips of lower densities so they should be able to get a decent discount.

    My last comment for you is this: the ATA specification is very well documented, and RAM is cheap. If people can interface PIC chips, HC11s, FPGAs, and other things to IDE, they someone could too. I wouldn't be terribly suprised if there was a project out there somewhere (shouldn't be TOO hard to do anyway) to basically turn a bunch of RAM into an IDE drive. Then all you'd need is some sort of battery to keep it going when the PC is off. Plus it'd be easily upgradeable.

    • See also FlashMemory.com.au [flashmemory.com.au]

      Larry

    • I wouldn't be terribly suprised if there was a project out there somewhere ... to basically turn a bunch of RAM into an IDE drive.

      I have seen products available that do this, but I don't have the slightest idea where it was or what it was called. And just to throw in another link for CF adapters, here [dansdata.com].
      • Quantum, for one, made a solid-state drive ("Quantum is no longer in the Solid State Disk (SSD) business, as of June 30, 2001."). I got to play with a 1GB version... basically just a bunch of DRAM in a drive form factor. Great for caching, temp space, etc... but it does dissapear when you power off (unlike FLASH/NVRAM).
    • Pcengines is where I've purchased my adaptors. I use them with cheap 8meg cards to boot previously floppy based computers and my tech support problems decreased quite a bit.

      The compactflash spec includes an ATA emulation built into the CF storage card - they look exactly like hard drives to the computer. There's little or no buffering, but they are generally faster than hard drives and much faster than floppies. They only manage a palty 1 million writes, though, so don't use them for swap or frequently changed files systems.

      -Adam
    • wouldn't be terribly suprised if there was a project out there somewhere (shouldn't be TOO hard to do anyway) to basically turn a bunch of RAM into an IDE drive.

      Device=[Path]RamDrive.sys [DiskSize [SectorSize [NumEntries]]] [/E | /A]

  • Why do they cost more? (Score:3, Insightful)

    by anthony_dipierro ( 543308 ) on Monday August 26, 2002 @08:15PM (#4145041) Journal
    Why do you want them more?
  • You do NOT want to use a compact flash card for a read/write file system; they have a limited number of write cycles.
  • They do have limited life spans. but how many reads and writes is that? and how many days/weeks etc... would that be in a pc? perhaps for low usage machines? maybe something more along these lines when IBM finishes that magnetic ram...
  • Because they are more expensive! Why could you not work that out ? **GRIN**

  • Just remember... (Score:2, Informative)

    by cpuwizard ( 171248 )
    Flash memory can only be written to approx. 100,000 times in any one spot before it will fail. Flash drives (and compact flash) will try to distribute the load, but if you have anything running that is caching to the drive it can wear out quickly. So things like the tmp directory should go in RAM.
  • The product you seek is a solid state hard drive [quantum.com]. AFAIK, they have been on the market for about 3-4 years, in not longer.

    This article [geek.com] might be of some use as far as pricing such an item. Also pretty cool talking about setting up a solid state raid, which is pretty absurd as far as going with the concept of trying to increase the speed; but with access times below .1 ms, it seems pretty sbsurd.

    This site [internetcloseouts.com] seems to have a price on some surplus quantum rushmores, but i dont know what a good price on these are, and therefore dont know what a good price would be.

    -D

    Links courtesy of google [google.com].

  • For a quiet (fanless) low-powered and small but inexpensive and complete PC (utp,serial,parallel,usb,vga,tv-out, etc.) you might want to check out the OpenBrick [openbrick.org]

    It boots off a Compact Flash card - FreeBSD and Mandrake images available, and optionally supports a HD

  • CompactFlash is produced in greater volume therefore it's cheaper. however CF to IDE adapters are about £20.
    The problem (as people has said) is that any flashmem based device wears out. The best thing to do is find out the average throughput of the unit (assume all of that are writes, worst case) and look at the write/erase cycle life, from there you can make a guess and how long you'd have until bits started failing.

    N.B. cheaper CF is often slower and fails quicker, be sure to check the stats before you buy.

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