Hewlett-Packard is to launch thin-client devices designed to help IT managers provide basic computing power for low-end users.

Thin-client computing is getting a fresh look from IT managers fed up with maintaining PCs for users who run a limited set of applications. Thin-client hardware sits on a user's desktop and provides a small amount of computing power and storage resources, but most of that user's computing needs are handled by a central server and coordinated by thin-client software.

Low acquisition costs and security are two of the primary reasons to consider a thin-client architecture, said Greg Schmidt, product marketing manager for HP. At around US$300 per device, HP's three new thin clients in its Compaq T5000 family are cheaper than low-end PCs. And since just about all of the user's data and applications sit on a central server, it becomes much easier for the IT department to update security policies or manage the rollout of new software by updating just one server, rather than a disparate network of PCs, he said.

This is recommended for groups of workers who use a limited and pre-defined set of applications, Schmidt said.

However, IT managers are conservative folk, and many fear they will be locked into an unfamiliar thin-client architecture if they move away from their traditional PCs, said Roger Kay, vice president of client computing for IDC.

"Even though you can demonstrate a lot of savings and benefits, it's different. IT departments decide to go with the fat client we know, rather than the thin-client we don't," Kay said.

In any event, around 80 percent of thin-client deployments wind up on a traditional PC, HP's Schmidt said. Some IT managers like the idea of centrally managing applications and security policies but want to give their employees the flexibility to download and work with a new application that requires more computing power, he said. Citrix Systems makes software that allows them to do this on existing PCs.

Another option for thin-client computing with a little more muscle is an emerging technology known as blade PCs. Blade PCs are similar to thin-client devices in that computing resources are centralised, but each user of a blade PC has their own dedicated processor and storage device like a standard PC. The blade PCs are stored in a cabinet in an IT department's server room, and are connected to the user's desktop through Ethernet cables and a small user interface box that resides on the desktop. ClearCube is a leader in the market for blade PCs, and HP also sells its own blade PC products.

Blade PCs overcome some of the performance complaints that have plagued thin-client rollouts and still give IT managers control over a user's security software and application deployment, Kay said. However, they don't offer the same performance as a mainstream desktop or notebook PC, and the IT manager still has to maintain individual pieces of hardware, he said.

HP's new thin clients are basic models designed as low-cost entries into server-based computing. The $239 t5125 comes with 32MB of flash memory for storage of drivers and small applications, and 128MB of DDR (double data rate) memory. The $289 t5520 features 64MB of flash memory and 128MB of system memory. Both come with Windows CE 5.0. The $319 t5525 is a Linux thin client with 256MB of flash memory and 128MB of system memory. The new devices will be available worldwide in mid-June.

HP switched to Via Technologies' processors for the t5520 and t5525 devices, Schmidt said. It had previously used Transmeta's Crusoe processors in all of its thin-client devices, but Transmeta is gradually exiting the processor business after years of losses.

The chip company has made arrangements to fulfil existing orders on older products, and HP will continue to use Transmeta's chips on its existing thin-client devices, Schmidt said.