[sp332]

Its TDP is 300W. It has a passive heatsink and relies on the server chassis having big loud fans pushing air from an air-conditioned cold aisle. Dual-slot PC cards seem to top out around 250W, with nvidia's 2080 Ti Founders Edition at 260W with vapor chamber cooling. AMD could go with a fancier cooling system, like the water cooler they put on the R9 Fury X, or they could slow it down to fit in a lower TDP.

[AstralStorm]

Current desktop Vega 64 can go almost 300W in LC versions. It can be pushed more with custom loops, easily 400W.

Source: actually owning Vega FE and tested overclocking using a custom loop. It can easily chew extra wattage when overvolted and overclocking while still staying stable. From performance per watt view, it is ridiculous though. Getting a 10% performance boost by doubling wattage over undervolted stock.