(Image credit: Microsoft) ,Following the announcement of Microsoft's Surface Laptop Ultra ahead of Computex , the company is announcing another device with the RTX Spark system on a chip at its developer conference, Build, in San Francisco. That new PC is the Surface RTX Spark Dev Box. With the company pushing Windows as a platform for agentic AI with Nvidia's new processor, the Surface-branded mini PC is set to run sustained workloads with a 100W thermal envelope — more than you can get in a laptop. Microsoft says that includes "long-running training jobs, agentic AI pipelines and local model fine-tuning." (Image credit: Microsoft) The PC has an aluminum chassis with 1,000 air vents in a grid, which looks a bit like the flat top of the Xbox Series X. The system features two USB Type-C ports, HDMI, USB-A, Ethernet, and a headphone jack. Nvidia states that the RTX Spark can deliver up to one petaflop of AI compute with 128GB of unified memory and can run models with up to 120 billion parameters locally.…