Valve and NVIDIA have entered into an agreement to collaborate on development, distribution and events, with Valve offering all NVIDIA gamers a free copy of Portal: First Slice.
Portal: First Slice is a special version of the regular game, and has been made available via the Steam distribution network. Visitors to Steam's website will receive a copy of the game if NVIDIA hardware is auto-detected.
A link to the Steam offer will also be included in all NVIDIA drivers.
"More Steam gamers, including myself, play on NVIDIA hardware than any other GPU," said Doug Lombardi, vice president of marketing at Valve.
"That's a testament to the company's long history of innovation and quality. By working together with NVIDIA to expand our development, distribution, and marketing efforts, we're increasing our ability to serve the millions of NVIDIA customers logging onto Steam and help us prepare for our next generation of content."
The companies plan to work together throughout the coming year to support competitive gaming events for Counter-Strike and Team Fortress 2.
"Valve's endorsement of our technology and tools is yet another example of how the world's leading gaming companies are working with NVIDIA," said Roy Taylor, vice president of content relations at NVIDIA.
"Portal is the hottest new, award-winning title from Valve, and we're delighted that Valve will offer First Slice exclusively to GeForce customers."