Almost two years ago I wrote about the catfight between disk and flash (see The Limits of Flash). It’s an entertaining market because we get to see the cut and thrust of the disk vs. semiconductor brawl at its rawest. I marveled then at thumb drive prices that were only $70 per GB down from $1000 per GB a few years earlier versus a disk drive at $40 per GB.

Rescan The Market
So this morning, when I saw that is offering a 4GB USB disk for $45 after rebate, I decided to check out the low-end of the thumb drive market. And sure enough, I found some end-of-life 4 GB flash drives online for $38, or $9.50 per GB. I marveled anew.

Flash’s Downside
Flash drives are much smaller, more rugged, lighter and, their downside for the cheapest drives, slower. High-performance flash drives use dual-channel controllers and two flash chips in a RAID-0 configuration to get higher performance and, since two chips cost more than one, are a little more expensive. What surprises me is what a lousy job the vendors do of educating people about these differences.

All Flash Drives Are NOT Created Equal
This is a price sensitive market, so many vendors source their chips on the spot market, so they really don’t know what combination of controller and memory chip they’ll have. Thus they don’t make many promises. The more expensive flash drives are lower volume and thus use the same components. You can tell difference because the vendor will usually make explicit performance claims.

Net Net: Disk Is Losing At The Low-End
The economic trends are clear and compelling. In less than two years, low-end flash prices have dropped by more than 85%. In the same period the competitive disk product price per GB dropped “only” a little more than 70%. IC economics vs mechanical device economics. Unless the disk guys figure out something great in the next few years, flash’s 15-20% annual price improvement over disk will keep it winning more business at higher capacities every year.

This is is going to be a long fight and us consumers will benefit enormously.

Comments welcome, as always.