I have my secondary rig now up and running (already have a 6700K, etc. for a primary box).
i5-6500
BeQuiet Pure Rock cooler
Core V21 case
ASRock Z170M Extreme4
16GB Crucial something-or-other 2400mhz DDR4
Radeon 5770
Samsung 830 128GB, BX100 250GB drives
Currently running 130mhz BCLK for 4.16ghz with Vcore set to Offset, +150mV, and VCCSA, VCCIO, and I think PCH all to 1.2v (from 0.95 or 1.05 defaults?). Crashed at +100mV Vcore. Haven't tweaked too much to see which of those voltages besides Vcore are really required since the last step before it stopped crashing was upping Vcore. I was able to get it to run at 105mhz on the stock cooler and 115mhz with the Pure Rock without even touching any voltage settings, just adjusting memory clock to be close to the rated speed. Didn't really test the limits, though.
HWMon shows about 1.28v nominal and 1.296v peak Vcore. I don't really care to push it a whole lot further, probably stop about the same as my other Skylake box around 1.32 or so which lets that run 4.7ghz, looking like I won't quite get that high on this one but 4.4ghz or so looks reasonable and is probably plenty fast for the OBS and general screwing around I'll be doing with this machine. Might eventually spring for a 750 Ti or something so it can at least do some light gaming, but this build is more for taking over to a friends place to screw around with OBS and green screening.