Sun Microsystems has unveiled a new version of its Sunray thin client that supports both the Windows, Linux and Solaris operating systems.

Thin client computers are cut down systems that lack a hard drive to store applications and operating systems locally. Programs and user data are centrally stored on servers, allowing users to log in and access their information from any location with network access.

Because thin clients do not run software, they are easy to maintain and update. Sun furthermore claims that the new systems use only five per cent of the power that a traditional desktop computer consumes.

The updated Sunray 2 comes in a basic configuration priced at $249 and a premium Sunray 2FS for $499. Both units are scheduled to ship later this quarter.

The premium model supports dual monitors and offers a build in fibre port for high speed networking. It is well suited for secure government workers and information workers such as software developers, Sun said.

The server maker first introduced the SunRay in 2001, but the appliance has had limited success. In addition to a lack of Windows support, network latency has proven to be a technical hurdle.

Latency causes a time delay between a user's command and the actual response on the screen. When a window is dragged to a new position, for instance, it can be a short while before it actually moves on the screen because the command and response have to travel through the network.

The worldwide market for thin clients however is gaining momentum, according to analyst firm IDC. The devices make up less than 1 per cent of overall desktop shipments, but are growing twice as fast as PCs. The analyst firm projected last year that by 2008, thin clients might account for a 10 per cent share of the enterprise client market.

Security concerns play a major role in the adoption of thin clients. Because of their centralised structure, it's easier to apply software updates while attackers have a harder time hacking into the network.