Im not seeing what you are using to cool with. That makes a HUGE difference. If its air, you wont get far, if its AIO you will get a little more maybe. To squeeze everything it has to offer you need at least a decent custom loop.

LLC of 7 is pushing it a bit high. Thing is it will overshoot before it settles out and that overshoot can be quite serious. I measured it with an Oscope on the terminals on the side of the board and about crapped when I saw the spike then the oscillation before it settled out. I generally try to keep it 4 or less.

Its not the voltage that causes degradation. Its the temps. I run an 18 core machine @ 4.7 to 4.8 and that puts me 75C to 85C with an AVX workload. I can run it up to 5.1 but that puts me into the 90s on the hottest core. Most of the time Im at 4.7GHz all cores with a static Vcore of 1.185, 4.8 takes 1.230. My cooling is a seriously overkill custom loop or Id never make it. I tried using an AIO to run it on the test bench before putting it in the case but that was a scratch. Best I could get was 4.4 all cores and it was hitting TDP and throttling at 4.5Ghz all cores. That H150i now lives in my wifes rig forever and I use a 480 rad with an Xres 140 for the test bench. before I install into the case.