Microsoft unveiled the Surface RTX Spark Dev Box at its Build conference, positioning it as a compact Windows workstation for local‑first AI development. Paired with the recently announced Surface Laptop Ultra, the new device targets developers who need to prototype, fine‑tune and run large models on‑premise before invoking cloud resources. The box promises a purpose‑built experience from hardware through OS to developer tools.

At its core lies the NVIDIA RTX Spark superchip, merging a Blackwell RTX GPU with a Grace CPU to deliver up to 1 petaflop of AI compute and 128 GB of unified memory. Microsoft claims the system can handle 120‑billion‑parameter models with a million‑token context at interactive speeds. An aluminium chassis doubles as a heatsink, ensuring consistent performance for long‑running training jobs and large‑model inference.

The device ships with Windows 11 Pro pre‑configured for developers: dark theme, simplified taskbar, Developer Mode, PowerShell 7 default, and WSL 2 with GPU passthrough. VS Code, GitHub Copilot, Python and Node.js are installed, while Microsoft’s AI Toolkit, Windows ML and Foundry link local work to cloud deployment. Secured‑core architecture, BitLocker and Defender secure sensitive models. It lands in the U.S. later this year via Microsoft.com.