[qes]

> Apart from having more thermal mass (takes longer to heat up/cool down)

_Much_ more thermal mass, and takes much longer to heat up and in most set ups will never reach the same temperature as the heatpipes in an air cooler - the waterblock will be cooler at idle and under load. I would think that larger temp delta allows heat to conduct away from the cpu package more quickly.

My 3960X sees 125MHz higher all core full load, almost 100MHz all core average work load, and 50MHz higher single core boost clocks under a custom loop (280+140 rads & Optimus TR3+ block) than under a Noctua NH-U14S TR4-SP3.