Why Do Flash Drives Cost So Much?

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."

Comments

PC104

[Oriumpor]

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.

Apples and Oranges.

[WasterDave]

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

Re:Apples and Oranges.

[MonMotha]

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).

IDE to Compact Flash and More

[MBCook]

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.

Re:IDE to Compact Flash and More

[stienman]

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

Why do they cost more?

[anthony_dipierro]

Why do you want them more?

Comparing Oranges to Oranges

[Nonesuch]

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.