I write computer programs, each is speed limited by something, some operate as fast as the hard disk can move data, some operate as fast as the CPU can execute instructions, some run as fast as RAM memory can fetch or store data, some run as fast as the operator can type, etc. But each is limited by something. (If I wrote for F@H, I would have GPU programs limited by the PCI-E bus)
I am old enough I wrote programs limited by floppy disk speed and by 110 baud serial port speeds, which are no longer issues.
F@H does not ask for operator input, and does not use much hard disk bandwidth. The clever designers have minimized time waiting to send and receive WUs over the internet. As the complexity of the proteins has advanced, so has the size of new CPU caches, so F@H is not as bound by RAM as you might suspect. (One reason older CPUs are so much slower is smaller cache sizes, so they become RAM speed limited) So often F@H is running as fast as your CPU can complete instructions. One reason A7 cores are faster than A4 cores is they use newer, more powerful instructions on new CPUs. On older CPUs, A7 is less impressive. while many modern CPUs can automatically throttle back if they encounter high temperatures, they do not throttle back to avoid high temps.
A fast video card working on a simple protein may spend a large fraction of a WU not limited by the GPU. PCI-E Bus speeds, CPU set up routines, more cores than atoms to simulate, etc. may lower GPU utilization. In some ideal future F@H may be able to partition the GPU for multiple tasks, but few cards have even taken baby steps toward that. (Dynamic load balancing scheduling system. This allows the scheduler to dynamically adjust the amount of the GPU assigned to multiple tasks, ensuring that the GPU remains saturated with work except when there is no more work that can safely be distributed to distribute. Nvidia therefore has safely enabled asynchronous compute in Pascal's driver.
https://en.wikipedia.org/wiki/Pascal_(m ... hitecture) may help F@H in the future )
So it is not easy or simple to slow a computer by doing less work. (it is easy to do less useful work, but that won't produce less power) rapid heating and cooling inherently means rapid expansion and contraction, so not only may one not use less power, if you do, your computer may not last as long.