The only way to know would be to test it with the configuration you buy -- there are too many variables that come into play, ranging from the hardware configuration to exactly what's running on the system.  It will be a fraction of the rated power output when the system is idle, but if it's heavily loaded, it will need a substantial power input to run properly.

If you're worried about your power bill/power draw, this probably isn't the system for you.

@ejn63​ Thank you for this advice.

The thought is that while the system will obviously draw a lot under heavy load, I don't consider it realistic that STH measured 195W as the idle consumption. A GPU will idle at less than 20W, a Xeon shouldn't use more than 20W when idling, U.2 SSDs will use about 5W each on idle (PCIe NVMes will use a fraction of that), and there isn't a whole lot else going on there when the system is idling.

Depending on who you ask, my current workstation draws 111W while I'm writing this (and uses 92W; information from the PSU) or it draws 80W (information from the remote-readable socket), and although it is a Core I9, not a Xeon, it shouldn't make such a difference.

I am trying to figure out if the STH measurement is sensible at all.

Edit: the configuration I have in mind is 12x16GB RAM, an air-cooled RTX 3080, 2xXeon Gold 6132, 2xPCIe-attached NVMe SSD.

With that hardware specs, you may consider the 7820 to if it could be lower in power draw.

@Chino de Oro​ Yes, that is true. The seller does not have that on offer, though, so no luck there. And while I have been pondering on the right brand to choose, they sold out their last T7920, as well, making this question irrelevant for the time being.