PC gamers who own NVIDIA's (NVDA 0.76%) latest graphics cards will soon have access to a number of new features, one of which had previously been exclusive to Sony's (SONY 0.37%) PlayStation 4. The update should make NVIDIA's cards more attractive, and help it further increase its market share dominance over rival AMD (AMD 0.69%).

NVIDIA introduces GameStream Co-Op
Owners of Sony's PlayStation 4 can take advantage of a feature called Share Play. It requires an active subscription to Sony's PlayStation Plus service, but allows PlayStation 4 owners to play games with friends online.

Of course, online multiplayer has existed for years, but Share Play is quite different. Rather than play against each other in Call of Duty matches or cooperatively in World of Warcraft, Share Play literally mimics the experience of playing a game with a friend in the same room on the same television. If it's a game designed for just one player, the host player can remotely "hand" their controller over to their friend.

NVIDIA's forthcoming update to Geforce Experience -- its driver software suite -- includes GameStream Co-Op, a service that functions almost identically to the PlayStation 4's Share Play. "GameStream Co-Op...lets you stream your game over the Internet to a friend and play together cooperatively -- just as if your friend was sitting in the chair next to you," NVIDIA writes.

NVIDIA's growing ecosystem of products and features
In the past, graphics cards were largely sold based on two factors: price and performance. But over the last few years, NVIDIA has been expanding the services and features exclusive to owners of its hardware, essentially building a sort of ecosystem around its cards.

GameStream Co-Op is the latest example, but just one in a long running series of advances. NVIDIA's Shield hardware -- which has included a tablet, handheld game console, and Android TV set-top box -- supports remote game streaming, allowing owners of NVIDIA's graphics cards to stream their PC games over the Internet to a corresponding Shield device -- a Shield set-top box attached to a TV in the den, perhaps, or a Shield tablet in a hotel room.

NVIDIA's G-Sync technology improves graphical fidelity when one of NVIDIA's cards is paired with a compatible G-Sync monitor. NVIDIA has also rolled out features that make it easier for owners of its cards to record and share gameplay (called Shadowplay), including broadcasting live to Twitch. In addition to GameStream Co-Op, its latest update includes support for YouTube -- NVIDIA gamers will soon be able to upload their recorded clips directly to the video platform.

NVIDIA is dominating AMD
NVIDIA's share of the graphics card market has surged in recent quarters. According to a recent report from John Peddie Research, NVIDIA's cards accounted for more than 81% of the graphics cards sold last quarter. That's up from 62% in the same quarter last year.

Given that the graphics card market is a duopoly, NVIDIA's gains have come at the expense of its sole rival, AMD. Demand for AMD's cards has tumbled, as its market share has fallen from 37.9% in the second quarter last year to just 18% last quarter.

AMD has mimicked many of NVIDIA's advances -- in place of G-Sync, it offers FreeSync; in place of Shadowplay, it offers Game DVR -- but these updates have come only months after NVIDIA's. Even then, AMD has not managed to fully keep pace -- it has no Shield equivalent.

Updates like GameStream Co-Op may seem relatively insignificant, but overall, these features help set NVIDIA's cards apart from AMD's. With its market share surging, PC gamers clearly care.