Well, I wouldn't say I have a beefy car or a beefy sword: there's some historical bit of linguistic connection that seems to have caused people to describe a server with the adjective "beefy", rather than "powerful", "hefty", "stacked", or... "chonky" ;P. Coming up with some options, I think my favorite might be "cranked"?
The first definition for beefy from Merriam-Webster is: heavily and powerfully built .
As someone who's had to rack some pretty heavy servers with lots of GPUs, CPUs, NVMe drives, and RAM, that turned out to be quite powerful, I'd say "beefy" is accurate.
Side note edit: hefty and chonky don't tell me much about power. Stacked is usually more about a team or group of things (and for individuals, I'd rather not see it).
