How to have lower vcore on AVX loads (negative offset) than on other loads?

Discussion in 'Overclocking & Cooling' started by chrisoutwright, Jul 10, 2019 at 3:31 PM.

  1. chrisoutwright

    chrisoutwright n00b

    I have an Asus Z270-A Mainboard and an i7 7700k.
    I have quite a hot 7700k and so far I can maintain 4.8/4.9 at about vcore 1.27-1.29, but despite my NH-D15 cooler that has been reseated just recently, my temps get over 80 in non AVX scenarios.
    For AVX loads I get over 95°C (for 1.28 vcore), despite having a multiplier of -2 for 4.9Ghz, which is because the vcore stays nearly the same as for non-AVX loads. At 4.7Ghz, AVX (etc.) instructions in Prime96 and Intel Burn Test run fine at vcore of at least 1.23-1.25, but all other loads require more.

    So, how can change the Asus BIOS settings, so that I have vcore for AVX loads at most 1.250v and for all others, say 1.280v?
    I haven't seen any guide do this and I am at a complete loss as every setting I have tried (adaptive mode with offset, offset alone, manual with LLC settings), I mostly get the opposite, AVX loads get slightly higher vcore whereas with Cinebench r15 load I get lower ones so that it crashes.

    I think having separate vcore settings are quite worthwhile when one has upper thermal limits that must not be overstepped, or is this procedure just dumb?
    Any ideas on how to do this with Asus MBs?

    So my problem is not AVX is not stable ( therefore the minus offset to make it stable) but the vcore with avx stable and temps acceptable is too low for non_avx loads that run at 4.9Ghz. Other overclockers mostly do the other route, upping vcore for AVX but having lower vcore for non AVX, which is not possible for me with my temps, and my route seems to suffice better for the system imo.

    Is there a way in terms of power throttling to get the result I want? For AVX, I have package power of 115w (IA core - 112w), and non AVX about 95w (IA core - 92w). So I would set PL1 to about 105w and PL2 to 95w? What happens then with vcore when AVX gets throttled to 95w?

    Would it also make sense to have a LLC with more vdroop (as for AVX it requires more power?) or will AVX loads have the same vdroop as other instruction sets?

    At the moment, I found that adaptive mode (overwrite 1.265 - Auto) gets me 1.264v max which is stable for both 4.7Ghz avx (due to LLC, I sometimes get 1.248 with AVX which is good!) and 4.9Ghz non-avx load.Let's see how the power throttling handles both. Interestingly, For Intel Burn Test (uses also AVX), vcore stays at 1.264v, but in prime95 it will go down to 1.248v.