Running PBO, temperature wise is probably the worst option. It overvolts the CPU so so much. Seeing 1.4-1.5v !!! on some cores it`s not rare. For illustration i can run 3.8GHz on all cores at 1.15v and get better temps then default PBO.
At 1.1-1.15v for all cores,the total CPU power consumption is around 275W, will get you 5850Cinebench.
Runing PBO will get you up to 300W, and get around 5200-5300 Cinebench.
So if we are talking purely about rendering performance, or 24/7 render loads, Manual OC is the way to go.
If you struggle with single tread performance or use poorly threaded applications,then PBO can help, but not much. Because, how much can you gain,going from 3.8 to 4.0-4.1 on those couple of cores that can take it..
btw, spent about a month bencharking 2990wx on Linux(ubuntu and mint) and it`s just ridiculous how much faster it is on Linux compared to Windows, some application, like Houdini, up to 30% on simulations(pyro/grains/).