My math (and google) shows a 300 mm diameter wafer, and 300,000,000 transistors/mm^2 So for $20,000 (in quantity) you get somewhere around 10 trillion transist

My math (and google) shows a 300 mm diameter wafer, and 300,000,000 transistors/mm^2 So for $20,000 (in quantity) you get somewhere around 10 trillion transistors? That's enough for about 50 4096x4096 multiply-accumulate chips. At a nice slow 1 Mhz clock rate, each would take about 3.5 watts, and give you 16 teraflops of performance. If you stepped up the power and cooling, you could likely get to 350 watts of power at 100 Mhz, and 1.6 Petaflops. 50 of those chips, for $20,000 --> $400 each