GPT-6 Astra Ultrafast is claimed to run on Nvidia Blackwell GPUs

A post claims Nvidia confirmed GPT-6 Astra Ultrafast runs on Blackwell GPUs and says Astra Ultrafast can deliver up to 8x faster token generation than Astra Standard. It also says OpenAI used internal models to optimize inference on Nvidia GPUs, including kernels built around Blackwell, and quotes OpenAI inference lead Philippe Tillet saying Astra can generate kernels that improve latency, throughput and cost on Nvidia hardware.