VirtenSys Ltd, the UK-based outfit that virtualizes off-the-shelf PCI Express switches, has picked up $16 million in C funding reportedly on the strength of the widgetry's traction, I/O being a critical bottleneck.

The money from existing investors Scottish Equity Partners (SEP), Celtic House Venture Partners (CHVP) and Gimv will be used to grow its revenues and broaden its markets and operations worldwide.

Its switches let servers be deployed completely disk-less and adapter-less. They are described as optimizing server networking and storage connectivity, and are supposed to be a catalyst in next-generation green IT data centers.

Gartner estimates the I/O virtualization switch opportunity is worth upwards of $4 billion a year.

Earlier this month, the company announced that its IOV switches support Ethernet, SAS/SATA and Fibre Channel, becoming the first company to consolidate and optimize the most commonly deployed networking and storage connectivity in servers. They create virtualized I/O Clouds where servers' I/O resources are pooled, consolidated and dynamically allocated on-demand based on application needs.