Hi, this with Intel Baseline Profile  I think it's running normal as it should be.. I don't know what you exactly did, but I think my results on 14900KF outperforming your 14900KS. I only ran the intel baseline profile and set the limits. that's al...

Try Fortnite, it usually show up fast  , and try cinebench with Multicore test...   please keep me updated 

And you are not restricting the processor, you are just setting the default intel values, while your mobo trying to overclock it which cause to instability/crashes..

You won't notice any performance lose. The only thing you will notice is cinebench score, but this doesn't mean it's performance lose 

But... I have 3 PCs 13900k 13900k 14900k   all of them are not stable, do you think RMA is the solution? short answer: nope