alt Hacker Newsso 1mm2 peppered by those cores at 300MHz will give you 4 Tflops. And whole 200mm wafer - 100 Petaflops, like 10 B200s, and just at less than $3K/wafer. Giving half area to memory we'll get 50 PFlops with 300Gb RAM. Power draw is like 10-20KW. So, giving these numbers i'd guess Cerebras has tremendous margin and is just printing money :)
Yes, assuming you don't need to connect anything together and that RAM is tinier than it really is, sure. At 28nm, 3megabits/square millimeter is what you get of SRAM, so an entire wafer only gets you ~12 gigabytes of memory.
And, of course, most of Cerebras' costs are NRE and the stuff like getting heat out of that wafer and power in.