I have exactly the same thought. In their PSU deep dive blog, they mentioned:
Although the “peak” power demand of the AMD Ryzen AI Max processor is 140W, it can actually pull hundreds of watts in millisecond-level bursts. Because there is no battery in the Framework Desktop to absorb this, we sized up the Power Supply to handle it and maximize performance.
I wonder what the exact numbers are.
ATX specs had this below. Assuming the HDplex 250W PSU sticks to ATX specs, then it should sustain 250W*135% = 337W for 10ms.
But anyway I’m not a professional electronics engineer, what do I know 
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