IntroductionSwitchable graphics on laptops, despite its obvious appeal, has always been a niche feature on laptops. Recently nVidia announced its intention to change this with its Optimus technology. All the Transformers quips have already been well-used, so we'll save you the wise-cracking and get into explaining this very cool technology.
Switchable Graphics: A Brief HistoryYou can trace switchable graphics' origins all the way back to the Sony VAIO SZ Series, which we first looked at in the form of the VGN-SZ2XP back in 2006. It combined Intel's integrated graphics with an nVidia Go 7400, but to switch between the two you had to flip a physical switch and then reboot your machine - a bit of a fuss for an ultimately small performance gain.
In recent times this has seen something of an improvement in the Asus UL50Vg, which while still requiring a physical switch, could make the switch without rebooting - instead the screen flashes for a moment or two.
Clearly the latter is a massive improvement, but even with this improvement nVidia's research discovered that among users who had a switchable graphics laptop only one per cent of users ever used it. Now the reasons for this could be numerous: some may not even know they have the feature; some may know about it but have no use for it, and some know about it, have used it, but then found that the discrete graphics isn't powerful enough to do what they want.
Of course, as you've probably heard in recent times, nVidia is big on persuading people that the GPU is becoming more important for general computing tasks, not just playing games. Be it accelerating video encoding through CUDA, HD video playback via DXVA (DirectX Video Acceleration) or Flash video, the GPU can be put to all sorts of uses. As such, getting switchable graphics to work in a useable, simple fashion is a big deal for them - particularly on ION netbooks, where the role of the GPU is amplified by the limited Atom CPU.
What is Optimus?Optimus is more or less the ideal end-game for switchable graphics. Instead of a physical switch, Optimus switches to the discrete GPU on-the-fly whenever it is required. This could be for a game, using a CUDA application (e.g. Badaboom) or for HD video decoding. And, when you're just writing the next fantasy novel bestseller, your system will automatically default to the low-power, integrated graphics.
Unless you take an active interest in this process, specifically selecting what programs you want to run on the discrete GPU or integrated graphics, the entire process is completely invisible to the end user. Most importantly, when the discrete GPU is inactive it is completely off and draws no power, thus ensuring the best possible battery life.
Intrigued? Read on to find out what makes it tick.