The 300 W rating is the real constraint. It puts the B770 above the 190 to 225 W band the page assigns to earlier Arc A770 and B-series cards. That forces a larger power budget, heavier cooling, and a board that cannot hide behind the older ceiling.

For buyers, the number changes the question from availability to chassis and PSU. For the fab, it marks a higher power class inside the consumer Arc stack.

The page lists roughly 32 Xe2 cores, 16 GB of GDDR6 on a 256-bit interface, and a full PCIe 5.0 x16 connection. It does not attach a picture or give clocks, memory bandwidth, yield, price, or frame rates. The document also does not prove whether the 32 Xe2 count is enabled at launch or whether an Arc Pro variant gets more than 16 GB.

The SYCL reference is software readiness, not a benchmark. Until a board is tested, the 300 W figure is a design limit, not a performance result.

The 300 W rating is the real constraint, and the SYCL appearance shows software preparation rather than performance.