> I definitely value lower power usage when idle. My desktop PC uses ~150W when idle.
These two statements appear to be in conflict. 150W is a high idle power consumption for a modern PC. Unless you have something like an internal RAID or have reached for the bottom of the barrel when choosing a power supply, 40W is on the high side for idle power consumption and many exist that will actually do ~10W.
In this context "modern PC" is pretty much anything since approximately Ivy Bridge. You can get one of those -- the entire machine -- for less than $50, and somewhat newer ones for around $100. If you're currently using something with a 150W idle power consumption on a regular basis, you're losing more than that in electricity.
These two statements appear to be in conflict. 150W is a high idle power consumption for a modern PC. Unless you have something like an internal RAID or have reached for the bottom of the barrel when choosing a power supply, 40W is on the high side for idle power consumption and many exist that will actually do ~10W.