Almost every CPU designed for a laptop includes an integrated graphics processor, a low-power chip that handles basic video duties. That “iGPU” doesn’t go away if your laptop also includes a discrete graphics card from AMD or Nvidia — in fact, you can use it instead of the more powerful card to save a bit of battery, in a setup called a “hybrid” laptop. Microsoft has a bit of technology that helps to smooth out the wrinkles of this double-GPU setup, effectively giving you more power and efficiency.
The company outlines its Cross Adapter Scan-Out system (CASO) in its latest dev blog post, spotted by VideoCardz.com. Essentially, the CASO software tweak allows a discrete graphics card to handle rendering and send the output frames directly to a laptop’s display, without needing to pass through the CPU’s integrated graphics system first. This allows your gaming laptop to more or less ignore the integrated graphics during sessions of gaming or other intense graphical processing.
Normally, the laptop’s integrated graphics becomes the “monkey in the middle,” and bypassing it results in less visual latency, less wasted battery power, and more system resources dedicated to the task at hand. It’s an ideal setup if you’re ready to put your machine into its highest performance mode, particularly if you’re plugged into power at the time.
CASO tech is basically a software solution to a similar hardware switch that both Nvidia and AMD have had for years, called a multiplexer or MUX. But because it is hardware-based, not every laptop with a discrete graphics card has one, particularly if it’s a non-gaming model that just happens to offer a GeForce or Radeon GPU upgrade over integrated graphics. Microsoft’s CASO gives some of that functionality to any user, providing that the laptop is from the last couple of years (Intel Core 11/AMD Ryzen 6000 or newer).
According to the Microsoft blog post, the CASO implementation can boost framerates in games by an average of 16 percent, with an even more impressive 27 percent reduction in display latency. Giving the discrete GPU a more direct rendering path even made the overall system more stable, resulting in fewer freezes and crashes. Not bad, especially for a free software tool that’s running behind the scenes in Windows.
Further reading: The best gaming laptops