Showing results for 
Search instead for 
Did you mean: 

5820K cache voltage and offset

Level 7
Hi all, first post and happy to be signed up and part of the community; here seems like a good place 🙂 I hope you don't mind clearing some things up for me about this chip. There's not a massive amount of info out there, it seems.

First, a bit of backstory.. I bought an Intel 5820K last year with an Asus X99-A motherboard and so far it's been great. I've been slowly tweaking it over time and settled on a conservative 4.4Ghz core at around 1.28 volts. I tried to get 4.5Ghz but gave up (temps were getting towards the mid-80s which is a bit too much for my liking); I cut my losses and hover around 70c mark full load using Corsair H110i.

The RoG guides have been great but there's still a few blanks I can't fill in when it comes to overclocking the cache. Random sources on the internet suggested keeping the cache voltage on this chip to around 1.25 volts, which achieved my 4.2Ghz cache/4.4ghz core frequency.

I would really like to get the cache synchronous with my core frequency but wanted to know

1) your opinions on raising my cache above 1.25 volts and where you consider a 'safe' cut off for cache voltage (how long is a piece of string - I know 😉 and

2) if you think I should clamp the cache (lower and upper bound) 'multipliers' to the same value, at a fixed cache frequency or should I let it scale? (am I right in thinking a BIOS update for this board changed the lower multi from x24 up to x30?)

I have been using cache voltage offset because I've been lead to believe adaptive cache voltage just flat out doesn't work.. am I right? I've been struggling to get my head around working out what my cache voltage offset should be, apart looking at the BIOS's 'resting' cache voltage and adding the appropriate mV to achieve the manual cache voltage from my stress tests.

3) What is adaptive voltage actually adding to? Is added onto an auto determined number the motherboard decides for the lowest cache multiplier?

I'd also like to hear other people's observations on what cache voltage does to temperatures, if anything.. A gap seems to be created in my package temperature readings from my core temps in Intel XTU when I increase cache voltage. But if I put the cache voltage back, the disparity is still there, making me think it's a software calibration problem, I don't know.

If you can shed any light on at least one of my questions I would appreciate it; maybe I can piece together if a few of you answer. Thanks for reading!