I've replaced the main fan in my PC, and it made things much quieter. I'll replace the fan in the power supply next; I'm doing one thing at a time so I can monitor the effect on system temperatures.
The Discovery Channel has been running some kind of Bike Week, and I've been watching The Great Biker Build-Off, as well as the usual Monster Garage and American Chopper. I find these shows endlessly fascinating. Such creativity on display. I could do without the bickering on American Chopper, though.
Back to the grind tomorrow...