Hard disk drives are becoming so inexpensive that prices alone--seemingly improbable a couple of years ago--garner headlines. So, how will speedy yet pricey solid-state drives keep up

Beyond the above-the-fold "2TB for $75" attention-getters for external hard drives, laptop hard disk costs have also been dropping like a rock, pushing mobile HDDs far below solid-state drives. The laptop market is one of the primary markets for flash memory-based SSDs, which are generally faster--in some cases much faster--than HDDs.

Case in point: the Hitachi Travelstar 7K500 HDD. The $64.99 price at Newegg.com not only gets you a 500GB capacity drive in a slim form factor but also one rated at 7200RPM--as fast as a laptop hard drive gets. Other goodies integrated into the drive include a 16MB cache and SATA 3 gigabit per second interface.

Apple still provides a good example of the price shock facing buyers who opt for an SSD over an HDD.

Two-figure pricing like that for laptop HDDs makes SSDs look like a luxury purchase by comparison. "HDD and NAND (flash memory) cost per gigabyte are destined to remain an order of magnitude apart for the foreseeable future. SSDs will remain from 10 to 20 times as expensive as HDDs of the same capacity," said Jim Handy, principal analyst at Objective Analysis, a firm that does semiconductor-related market research.

Look no further than Apple for the price shock that buyers face when opting for an SSD. In its MacBook Pro line, upgrading from a 320GB HDD to a 256GB SSD adds $650 to the cost of the system. And this has been the status quo for some time.

Prices are a bit lower for retail SSDs from top-tier suppliers such as Crucial, an arm of memory chip and SSD manufacturer Micron Technology. At $514.99, Crucial offers a better deal than Apple on a cutting-edge 256GB SSD with a high-speed 6Gbps interface. Still, that doesn't get anywhere close to HDD pricing at that capacity. (Note this does not include SSD pricing from second- and third-tier vendors.)

"SSDs will not gain prominence in PCs as long as consumers continue to fixate on price and HDD capacity at the same time," said Handy.

Plummeting HDD prices may level off a bit, though, in the wake of the planned acquisition of Hitachi's hard drive unit by Western Digital. "One of the consequences of the WD acquisition of [Hitachi's storage business] will likely be a reduction in the decline of average HDD prices," said Thomas Coughlin of Coughlin Associates, a data storage consulting firm.