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Why Do Flash Drives Cost So Much?

Posted by Cliff on 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."

22 of 45 comments (clear)

  1. Data rates by Drakon · · Score: 2, Informative

    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

    --
    Buttsex.
    1. Re:Data rates by singularity · · Score: 2

      One thing to do to speed up Compact Flash is to get a Firewire CF drive. It will not bring it up to Flash drive speed, but the limiting speed will be the card, and not the interface.

      --
      - (c) 2018 Hank Zimmerman
    2. Re:Data rates by NoMoreNicksLeft · · Score: 2

      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.

    3. Re:Data rates by tswinzig · · Score: 2

      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?

      --

      "And like that ... he's gone."
  2. PC104 by Oriumpor · · Score: 3, Interesting

    From what I've seen , and what the guys at wearables 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.

  3. Speaking of compact flash by dozer · · Score: 2, Interesting

    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.

    1. Re:Speaking of compact flash by MonMotha · · Score: 2, Informative

      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...

  4. Apples and Oranges. by WasterDave · · Score: 4, Informative

    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

    --
    I write a blog now, you should be afraid.
    1. Re:Apples and Oranges. by MonMotha · · Score: 3, Interesting

      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).

  5. IDE to Compact Flash and More by MBCook · · Score: 5, Informative
    After a quick search on google, I found this link. 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.

    --
    Comment forecast: Bits of genius surrounded by a sea of mediocrity.
    1. Re:IDE to Compact Flash and More by LarryRiedel · · Score: 2, Informative
      See also FlashMemory.com.au

      Larry

    2. Re:IDE to Compact Flash and More by silicon_synapse · · Score: 2, Funny

      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.

    3. Re:IDE to Compact Flash and More by stienman · · Score: 3, Interesting

      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

    4. Re:IDE to Compact Flash and More by DNS-and-BIND · · Score: 2
      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]

      --
      Shutting down free speech with violence isn't fighting fascism. It IS fascism!
  6. Why do they cost more? by anthony_dipierro · · Score: 3, Insightful

    Why do you want them more?

  7. Compact flash has limited write cycles by larse · · Score: 2, Informative

    You do NOT want to use a compact flash card for a read/write file system; they have a limited number of write cycles.

  8. Comparing Oranges to Oranges by Nonesuch · · Score: 3, Informative
    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

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

    --

    I do not deploy Linux. Ever.
  9. Just remember... by cpuwizard · · Score: 2, Informative

    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.

  10. Go away troll boy... by Andy+Dodd · · Score: 2

    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)

    --
    retrorocket.o not found, launch anyway?
  11. Re:I'd say... by penguinboy · · Score: 2

    Are you trying to use "solid state" as a synonym for "non volatile"?

  12. Re:ram & ide drive by Matt_Bennett · · Score: 2

    Two reasons- power and refresh- back when 4M sticks were common- the ram was pretty power hungry, if i remember right, it was about 1W/MB (at 5V). Even if that estimate is really high, it would still take a lot of power to keep up a whole drive worth of DRAM. The second reason is that the "D" in DRAM stands for dynamic- it is really just a single capacitor that drains off rather quickly- on the order of milliseconds, generally. You need to have something read the memory cell, and rewrite it. You really want SRAM- or static ram, but that takes 4 transistors/bit of memory, so they tend to be much less space efficient (and more expensive) than DRAM (which only needs 1 transistor/bit). SRAM doesn't need refreshing, and in general, as long as you aren't reading or writing to it, the current draw is really low.

  13. "solid state" memory confusion by geoswan · · Score: 2
    Are you trying to use "solid state" as a synonym for "non volatile"?

    I am going to guess that a momentary loss of attention caused c0ldfusion to write "solid state" memory when he or she meant "static" memory.