Help with a UEFI setting. (Core Ratio Extension Limit)

whoisit

Ars Tribunus Angusticlavius
6,565
Subscriptor
My Google-Fu has failed me. I have a setting in my systems UEFI that has me a little stumped. It is Core Ratio Extension Limit. It has a option of enabled or disabled. All the the description says is Disabled sets it to OCMB 0X1 = 85 and Enabled sets OCMB 0x1 = 120. And of course the UEFI says see the manual for more information, and the manual gives the exact same description as the UEFI and nothing more. My Googling has returned a lot of hits from the various manual archive sites and overclocking sites talking about different core and ring ratio settings, but nothing referencing these exact words. So does anyone here know what the hell it is?

Motherboard:
ASRock Z-590 Steel Legend
11700K CPU
 

Lord Evermore

Ars Scholae Palatinae
1,490
Subscriptor++
Searched Core Ratio Extension Limit "ocmb" and core ratio "ocmb" and nothing but PDF manuals came up, but I think that's enough to help with the different wordings from a few of them. This controls how much of an overclocking ratio you can have between the cores and the ring bus. Normally you can only overclock the cores up to 85x the bus speed (with it limited to that by default to prevent any automatic overclocks that might cause damage or highly likely instability), but if you happen to have a REALLY good CPU, it might be able to handle much higher ratios on at least some cores or even all cores. So you could apply this setting and then either set all cores to a ratio higher than 85X, or change the setting to allow per-core ratios and manually adjust the per-core ratios to exceed 85.

This would allow you to max out your bus speed, and then be able to get every individual core up to its own very highest speed even if it is more than an 85x ratio. Or the more likely scenario, if the ring bus speed can't be raised very much or at all (because this can cause instability or even latency penalties in communication with other components on the bus), you might still be able to crank up the clock speed on the cores higher than 85x and get a better boost than the default.
 
  • Like
Reactions: whoisit