Thank you for inspiring me to go the network-render route !!

FWIW, setting '128+128' or, sweet-spot '64+64', on this CAD-Tower woke all its 8 available threads, so ran 5x faster in CPU-only render mode. Makes 'quickie' set-up and scene tests that much less tedious...

"Synchronised Staring Team" ( networked to Box, ~95% CPU, ~½ hr progressive Superfly render )