IBM has unveiled a new server chipset that allows users to run a virtualisation hypervisor off a USB memory key instead of requiring it to be installed on a hard drive.

The Flash memory feature is enabled by adding a USB connector to the motherboard of IBM's new X4 server chipset.

Big Blue unveiled the chipset on Wednesday at a press event marking the launch of Intel's multi-processor quad-core Xeon chips. It is scheduled to ship in October and will support up to 16 sockets. Intel's 7300 chipset is limited to four sockets.

IBM plans to ship memory keys with a choice of hypervisors, including VMware ESX, Xen-enabled Linux distributions and Windows Server 2008 with Viridian, once it is launched some time next year.

The software will be tailored for use on the new systems, making it easier to set up new servers.

In a simplified view of the IBM system, users could set up new servers by plugging in a hard drive with their virtual images and booting the server of the USB drive. The reality, however, will require slightly more customisation.

Jay Bretzman, manager for product marketing at IBM, admitted that the overall benefits will be limited to setting up new servers.

"You do not get a lot of premium out of the fact that we put it on a USB key, " Bretzman told vnunet.com in an interview. "It is just simplifying the deployment of new servers."

Hypervisors currently have to be installed on a system's hard drive. Users can plug in the USB tokens into different servers while the virtual images are kept on the hard drive.

Theoretically, a company could choose to run their virtual systems on a Red Hat Enterprise Server platform one day, and switch to Windows Server 2008 with Viridian the next day.

On a desktop computer, running the operating system off Flash memory reduces system boot time as data is loaded into the system's memory.

But servers do not reboot on a regular basis, so running the hypervisor off Flash does not offer any major performance gains.

During a keynote at Linuxworld in San Francisco last month, Dell chief technology officer Kevin Kettler suggested that he too might create servers that run hypervisors directly off Flash memory. Dell, however, has been sparse on details.