Did you build your PC yourself? What is it?

[mansr]

My ageing PC currently (most parts have been replaced/upgraded at some point) consists of a Gigabyte water cooled motherboard, Intel i7-940 CPU, 24GB Corsair RAM, 2x fanless Nvidia graphics cards, 2x Intel NICs, 4x 4TB Seagate Enterprise disks, fanless Seasonic PSU, all in a Zalman case with integrated water cooling. This machine stores all my music, but it is also my main workstation.

[mansr]

1 hour ago, Keith_W said:

Interestingly, nobody here seems to talk about cooling motherboard MOSFET's which can vary their output depending on CPU load, and thus vary the amount of heat they produce, and thus introduce voltage irregularity due to the heat effect on MOSFET's. 

I'm not sure I understand your concern. Those MOSFETs are part of the voltage regulators for the CPU. Whatever variation in voltage they produce must be within the tolerances of the load, or the system wouldn't work. Also, they are typically cooled in way or another. At minimum, they'll have a heat sink mounted. On my motherboard, they are connected with a heat pipe to a water block which also cools the main chipset.

1 hour ago, Keith_W said:

Does nobody here own a watercooled PC setup?

I do, as I mentioned above.

56 minutes ago, Jud said:

- Do you have information about noise levels from water pumps and (if any) radiator fans?

Water pumps are typically nearly silent. My case has a 240 mm variable speed radiator fan. At the highest speed, it is definitely audible but not (to me) annoyingly so. At the lower speeds it makes very little noise. Getting noise levels down was my main reason for using water cooling.

56 minutes ago, Jud said:

Another general inquiry:

 

- Are you concerned about water cooling, and is that why you are asking if others have done it?  (I have always had an instinctive aversion to water around electronics, but have no hard data about failure rates from various manufacturers.)

Water cooling systems use deionised water with an anti-corrosion additive (similar to antifreeze for cars). A minor splash on a circuit board is quite harmless. As for reliability, I can only offer anecdotally that my current system has been running continuously since 2009 and has yet to fail. Hard drives fail more often.