If you're in any doubt that flash memory-based solid-state disks are on a course to quickly replace hard-disk drives in laptops, just take a look along the aisles of this year's Computex trade show.

Solid-state disks and machines containing them are plentiful at the show, which brings together the world's most important manufacturers and component makers with buyers from around the world, and is a good gauge of the direction of the industry.

That solid-state disks are replacing hard-disk drives shouldn't come as a total surprise: they're lighter, quieter, use less power and are sturdier than hard drives. The transition is being accelerated by fast price drops in the flash market. For example, an 8GB chip that cost $11.36 at the end of 2006 currently costs $8.47 on the spot market. That's a drop of 25 per cent in six months.

For example, SanDisk debuted its first SSD, a 32GB model, at January's CES but a mere six months on at Computex it's showing a 64GB model. The company says much higher-capacity drives are possible today but will be too expensive for most enterprise users, so it's increasing the capacity of its drives while keeping them at what it considers the sweet-spot of price and storage space.

Like SSDs from competitors, the SanDisk drives are offered as drop-in replacements for 1.8-inch and 2.5-inch hard-disk drives and so can be offered by system makers without the need for any modifications. As SSDs become more common the company believes smaller form-factor drives will be used in machines specifically produced for solid-state storage.

"The old technology of the hard disk is going to go away from the mobile PC market and be replaced by solid state media," said Doreet Oren, director of product marketing at SanDisk's computing solutions division in Israel.

Some analysts agree. In a report issued in May, iSuppli said it expects 24 million laptops sold in the fourth quarter of 2009 - about 60 per cent of the anticipated market - will have flash storage, versus less than 1 per cent in the last quarter of 2006.

Also on show at Computex is a wide range of solid-state disks intended for the industrial sector. Such drives are targeted at military and aviation applications and began replacing other storage methods several years before their entry into the PC market, thanks to the willingness of such customers to pay higher prices.

Apacer Technology is demonstrating a 128GB industrial SSD that can replace a 2.5-inch hard drive and operate at temperatures between -40 degrees Celsius and 85 degrees Celsius. It will be available in the fourth quarter, and a second version with double the data read speed of 200Mbps (bits per second) will be available in early 2008.

Alongside it was a flash-based RAID (redundant array of independent, or inexpensive, disks) drive which has two Compact Flash card slots. The capacity depends on the cards used.

It's not only in the SSD arena that storage advances are on show at Computex.

Toshiba has the latest in its line of 1.8-inch hard-disk drives, a model that can store 100GB, on show. The drive can be fitted into portable media devices, like the iPod, or ultra portable PCs. Toshiba is also using Computex to unveil its first HD DVD rewriter drive for laptops. A single-layer HD DVD-RW disc can store up to 20GB of information, which is just over four times the capacity of an equivalent DVD.

Hitachi Global Storage Technologies has its 1TB drive that was unveiled at CES and new at the show is a 250GB 2.5-inch drive for laptops. The 5K250 includes drive-level encryption and has 56 per cent more storage space than its predecessor, the 160GB 5K160.