In an era where an increasing number of laptops are equipped with dual graphics cards, one integrated into the processor (iGPU) and the other being a dedicated graphics card (dGPU), Microsoft has devised a solution known as CASO to maximize their combined potential.
Typically, laptops feature iGPUs that are directly linked to the display, while dGPUs handle rendering tasks, ultimately transmitting the images to the integrated graphics for display. This configuration is designed to strike a balance between performance and energy efficiency, with dGPUs reserved for demanding tasks and energy savings achieved through the use of integrated graphics. However, this two-step process can sometimes result in a loss of performance.
The Challenge:
Integrated graphics within processors, despite considerable advancements, remain relatively limited in power when compared to dedicated models. Furthermore, iGPUs draw from system memory (RAM) as they lack dedicated VRAM, which can impact performance.
The need for the dGPU to relay images to the integrated graphics for display introduces a bottleneck into the process.
Existing Solutions:
To address these challenges, AMD introduced Smart Access Graphics, and NVIDIA introduced Advanced Optimus, both leveraging a multiplexer (mux) to optimize performance. In this setup, the dGPU handles resource-intensive gaming tasks, while the iGPU manages less demanding everyday activities, ensuring smoother performance by eliminating the need for data transfer between the two graphics components.
However, laptops without a mux or with this function disabled may face limitations. Utilizing the dGPU can lead to increased energy consumption and reduced battery life.
Introducing CASO:
Microsoft’s solution for laptops lacking a mux or with disabled mux functionality is CASO (Catalyst Access for Systems Optimization). CASO operates by capturing a copy of rendered images, effectively boosting FPS and reducing display latency. This approach enhances performance without requiring additional hardware components.
Microsoft claims that CASO can deliver up to a 16% increase in FPS and a 27% reduction in latency. Additionally, it reduces recovery events and wait time detection by as much as 45%.
Noteworthy Features
CASO is not entirely new, having been introduced in 2021 for games with DirectX 11 support. However, its significance has grown as it now supports games with DirectX 12.
CASO is natively integrated into Windows 11, becoming an integral part of the operating system. Remarkably, it imposes no specific requirements and works seamlessly with any dedicated graphics card. Furthermore, it operates natively on any compatible device.
Compatibility
NVIDIA confirms that CASO works with all its GeForce graphics cards featuring the r515 driver or later. Intel‘s Xe Graphics with WDDM 3.0 drivers offer full support, and AMD’s Radeon 6000 series and newer are compatible when paired with the WDDM 3.1 driver.
CASO represents a promising tool for enhancing graphics performance on laptops without the need for costly hardware upgrades, offering a significant boost in performance and reducing latency.