5900x PBO Undervolt

[rmgdnz]

Hey everyone, 

 

Been messing around with my 5900x for a while and I noticed something interesting. I use PBO +200, motherboard limits, and a negative offset. I can run stable at all cores -30, except my best core that needs -20. When I do this, I notice that my second best core actually becomes my best core (second best core peaks at 5.075-5.11GHz and best core around 5.025-5.05). When stability testing earlier, -30 on all cores including the unstable one basically ended up swapping the performance (so 5.1 on best core, 5.05 on second best). 

 

Why does my best core seem to need more voltage while performing worse than my second best core? Does this mean the AMD designated best cores may be incorrect?

 

Note: I did make sure that -30 on all cores except my best core was stable, idling and lightly threaded tasks as well as heavy tasks work perfectly fine.

 

[freeagent]

1.475 is nothing to worry about.. How warm is it running?

 

 

[YoungBlade]

11 hours ago, rmgdnz said:

Why does my best core seem to need more voltage while performing worse than my second best core? Does this mean the AMD designated best cores may be incorrect?

The designated best cores are just the ones that Windows is going to prioritize using. It really doesn't mean much in this context, except that the core is going to be worked harder and so may need a bit more voltage to remain stable. It's also based on the stock config, so as soon as you start to OC/UV, all bets are off as to the accuracy of that.

[rmgdnz]

12 hours ago, YoungBlade said:

The designated best cores are just the ones that Windows is going to prioritize using. It really doesn't mean much in this context, except that the core is going to be worked harder and so may need a bit more voltage to remain stable. It's also based on the stock config, so as soon as you start to OC/UV, all bets are off as to the accuracy of that.

I see, thanks for the info.

[rmgdnz]

12 hours ago, freeagent said:

1.475 is nothing to worry about.. How warm is it running?

I actually was not referring to being worried about voltage/temps, but out of curiosity, what settings do you have enabled in bios/etc since I see you have really nice boost clocks? Also, your temps look great, did you do anything special or is it just good cooling and low ambient temps?