Locking the desktop in the filing cabinet

The disadvantages are a cost per seat greater than that of thin client -- where one server can be spread across multiple users -- and a reliance on one particular vendor's PC hardware, leading to lock-in and potential problems when upgrades are next due. Blade desktops do accept standard memory and disk upgrades, but lack standard PCI expansion slots.

American company ClearCube Technology was first to sell desktop blade systems. The company has installed desktop blade systems at financial institutions and at some military installations. IBM has resold some ClearCube systems, but HP is the first major manufacturer to develop and market its own blade-based desktop system as part of its Consolidated Client Infrastructure (CCI) initiative. So far, the blade concept has been mostly used to squeeze servers and communication equipment more efficiently into racks, but HP makes the case for extending the idea into desktop systems to help patch, licence and OS installation management, ease back-up and restore problems, and to maintain locality of sensitive data -- that is, to stop users making copies of secure data in insecure places.

Some of these ideas are reflected in lower management costs and, say desktop blade systems makers, in a lower total cost of ownership. However, it is hard to show significant TCO reduction in many instances, making desktop blades most attractive for the increase in reliability and decrease in downtime they promise. The idea is that if an individual blade does develop problems, it is faster and easier for a centralised support team to find and fix the issue if everything's in one place -- and as they appear to the network to be normal PCs, it is also easy to apply standard failover and management approaches to them. ClearCube is more aggressive about claims of downtime and cost reduction, saying that with its hotswap technology, a user will experience 99.9% availability and operating costs will be reduced by "at least 40%".

Desktop blades are unlikely to become a major feature on the enterprise hardware landscape in the near future, if only because of lock-in worries and the lack of flexibility they can bring. If the industry can standardise their physical attributes and manageability, so that blades from one maker can be swapped with those from another without trouble, then IT managers may feel they are sacrificing fewer future options and will be more comfortable with moving to this architecture. There will always be installations where the increased physical and electronic security and reliability of blade desktops will be recommendation enough: conversely, there are plenty of situations where the idea is not attractive. For the average IT manager, however, the TCO and manageability claims will need substantial proof before desktop blades become an attractive option.