Surface Laptop Ultra runs $2,599 to $5,899, and the petaflop is FP4

Microsoft launched the Surface Laptop Ultra on 7 October and the reviews are in. The machine pairs a 20-core Nvidia Grace processor with a Blackwell RTX graphics part and up to 128GB of LPDDR5X unified memory, behind a 15-inch mini-LED screen running 120Hz at up to 2,000 nits.

What it costs

The price ladder runs from $2,599 to $5,899. The entry machine carries 24GB of memory, a 512GB drive and an 18-core part with 5,120 GPU cores. The top one carries 128GB, a 1TB drive and 6,144 GPU cores. The difference costs $3,300 for 104GB of memory, half a terabyte of storage and 1,024 more GPU cores, which works out at $31.7 per gigabyte of RAM before counting anything else.

“Up to 15 hours of local video playback and up to 12 hours of active web use”

— Microsoft, Stated battery life for the Surface Laptop Ultra

Microsoft quotes 15 hours of local video and 12 hours of web use, and says the machine keeps 99% of its performance while unplugged. That last claim is the one to test first on any laptop built around a desktop-class GPU, because throttling on battery is where these machines usually give the hours back.

What the petaflop means

The platform is marketed on one petaflop of throughput at FP4, the four-bit format, rather than on a conventional NPU rating. The NPU itself runs 50 TOPS against the 40 TOPS Microsoft requires for Copilot+ features, a 25% margin. We made the same point about the desk box in October, where the petaflop was counted the same way.

Memory is what an LLM needs before anything else. A 70-billion-parameter model quantised to four bits needs roughly 40GB, so the 128GB configuration holds one with room for the operating system and the work beside it. That is the argument for a $5,899 laptop over a cheap one plus an API key, and it only pays off for someone who runs models rather than calls them.

For most jobs the hosted option still wins on price. Our catalogue of AI services puts the median paid entry at $15 a month, so the gap between the top Surface and the base one buys eighteen years of a mid-tier subscription.

What settles next

Three things settle in the next month. Sustained performance under load rather than the first benchmark run. The real battery figure with a local model loaded. And whether the Copilot+ features that justify the NPU arrive before the warranty does.

Informational material, not a purchase recommendation. Battery and throughput figures come from the manufacturer and early reviews, and sustained load tells a different story from a first benchmark run.