SRS BZNS! 128G, 32 threads, 16 bays
The Serious Business packs 128GB of DDR4 ECC RAM, 32 CPU threads, and sixteen 3.5" hot-swap bays into a 3u rackmount chassis weighing in at 75 pounds empty. This isn't an exercise in burning money—it's a pretty reasonable design for a small- to mid-size business hosting local infrastructure to service 20 or more (sometimes many more) employees. But it would be a pants-on-head crazy kind of thing to have sitting in your home or apartment.
We jumped off the Intel train for this build, because when you want real horsepower, AMD's Epyc CPUs are a much better buy than Intel's Xeon Silver or Gold. The Epyc 7281 we chose here features 16 cores and 32 threads, with significantly better multi-threaded performance than a Xeon Silver 4114 costing about $100 more. The Xeon Silver is a little faster per-thread than the Epyc, but a whopping 12 extra threads more than makes up the difference for the kinds of workload a server like this is most likely to see—lots of users, and probably lots of VMs, too. (You could shave about $120 off the cost by dropping to an Epyc 7251 with eight cores and 16 threads, but your bang-for-the-buck goes down significantly if you do.)
Our Supermicro rackmount chassis comes with its own 800W redundant power supply; you can plug each module into a separate UPS, which allows you to hot-swap the UPSes when they need battery replacements every few years. What you can't get out of this beast is anything approaching silence. It's fine in a server room, but if you try to share an office with this thing it'll drive you batty—don't say I didn't warn you. (On the plus side, all those redundant fans mean that the monstrous passive heatsink we picked for a cooler is plenty.)
