Please take the poll to post what vCore it took to achieve stability in P3D for your 9900K@5Ghz.  Not 5.1Ghz or other, but 5.0Ghz please.  Round up to the next 100ths of a volt please.  I thought I had it nailed down but had a couple of what appeared to be overclocking-related crashes just in the past week and would like to know what it took to achieve stability in P3D. 

Edited May 4, 20206 yr by Noel

I just have mine set to auto.  Never have touched BIOS except for MCE.  It runs 5.0 on all cores with HT off.  Gets too hot with HT enabled for me but I use air cooling.

No one is hitting 5GHz on all cores at any of the voltages in the top 3/4 of the poll.  Not with a real workload anyway.  Booting to the desktop doesn't = stable.  My own 9900k is a *good* chip and it requires 1.3V for 5GHz on all cores.  

Whoever it is that chose <= 1.15V: you're wrong.  Zero chance you are correct.  Pull up a real workload like Handbrake (or a synthetic benchmark such as Realbench that simulates this workload).  Guaranteed crash.  

Disabling HT is good for a reduction of 2 or 3 hundredths of a volt, but even with that you're still going to need voltage that is at least in the mid-high 1.2x volt range on a good chip.  

Edited May 5, 20206 yr by TechguyMaxC

That was me at 1.205v for 5Ghz on all cores and that with running Realbench.  And prior to finding out what vCore was sufficient for 5.0Ghz I was using [email protected], which is tempting to continue using as it's only 4% faster in raw clockspeed.   I'm guessing 1.205v is not a significant stressor on this CPU as I hope to keep it for another 6 years.  Low temps at peak load.  Poll your 1.3v if you like it would be nice over time to see what's working for people, but you are right there will be responders who aren't really entering accurate information.