Thanks for replying. And for suggestions from both of you.
I have HWiNFO64 installed too, but I was watching the Active Clocks window (which shows the same clocks as Afterburner), instead of Core Effective Clocks. But you're right, effective clocks are something entirely different. They rarely go into the 4Ghz range, let alone in the high 5Ghz, while Afterburner shows my P-cores are always in the 5.7-5.8Ghz range and my E-cores @4.6Ghz. So that explains the loss in performance I guess.
As for the Undervolt Protection setting, it's actually *disabled* (by default). I checked that setting even before I did any undervolting as I know it's a crucial step to do. But even if that setting was enabled, that would still not explain why multi-core tests are all fine. Running all cores at such a large negative offset should be even harder than a single core, no?
I will try to undervolt using the adaptive mode, while checking the core effective clocks. And I will also check out BenchMate, tho I have many of these tools already installed.
UVP is actually disabled, but I wonder what you meant with "cpu (ME)"? Intel Management Engine? I read that it indeed can conflict with undervolting.
While reading I also found out that some CPU microcode patch was disabling undervolting of the Intel CPUs in the past.. I just hope the recent microcode update (0x129) doesn't have something to do with my issue, because before I updated my BIOS last month, I could only set waaay lower undervolt. But could be something else too, as I've skipped a few BIOS versions before that one.
EDIT:
Actually, we're both right and wrong regarding the undervolt protection setting. Although the option is disabled, there's *another* related setting called "IA CEP" that has the same hate towards undervolting
(there are some interesting articles about it on the net)
Now that I've disabled IA CEP, this is my new single-core score:
View attachment 362447
Me happy! 130%+ increase with only one option disabled
Plus I had to dial down offset voltage by 20 mV.