This is absolutely **NOT** a good idea!
This works in Apex Legends because Apex Legends does not put a high amp load on the VRM's, which limits guardband penalty and transient response is not affected as much. LLC8 (aka Ultra Extreme loadline calibration on Gigabyte boards and Mode 1 LLC on MSI and Asrock) use a 0 mOhm loadline, which in theory prevents load voltage from dropping below idle. (the way vdroop works is this formula: I * R = vdroop, where I=current in amps and R=resistance (mOhms). So for example 150 amps * 0= 0mv vdroop. (It's actually 0.01 mOhms) but there is a very serious problem.
VRM's do not respond to 0 mOhms loadline gracefully, because MOSFETS cannot charge and discharge their capacitors fast enough to change power (wattage) loads the CPU is requiring as the CPU responds MUCH MUCH faster than VRM's (we already know how fast CPU's can respond, while VRM's usually operate at 500 khz switching frequency). And its not just the voltage the VRMs must adjust down from +12v, there's the *current* (which leads to watts, as watts=volts * amps) also that has to be released by the mosfets too! These are designed to operate with a loadline (vdroop), so that when the CPU goes from an idle state to a load state, or a load state to an idle state, the VRMs and caps are given time to charge and discharge, to adjust the current to what the CPU is needing.
When you have a 0 mOhm loadline, there is *no* time at all for the VRM's to respond to a change in CPU load (to adjust the current it's supplying to the CPU, which the CPU burns up as watts). This causes problems. For example: If a CPU is operating at a heavy load, let's say 150 amps, shall we? E.g. running Prime95 with AVX small FFT (29.8 build 3), and running at 5 ghz, 1.30v, with Level 8 LLC, Ultra Extreme, whatever. Then that load stops (change in iteration, super fast calculation load change, etc or even stopping the test). The CPU responds instantly. The load is stopped. But the VRM's? The VRM's can respond nowhere NEAR that close. So that means, for around something like 45 *Microseconds* or so, the VRM's are still supplying 150 amps of current to the CPU! But the CPU is not using those amps anymore. Power cannot be created nor destroyed It cant be released as heat since heat is a byproduct of watts. So what happens? The voltage spikes up *hard*. It's so fast that a digital multimeter can't pick it up. You need an oscilloscope to see it. But these spikes, at heavier loads, can exceed *200mv* on cheaper motherboards that have bad transient response! So that 1.3v becomes 1.5v. This is worst case scenario (full load to no load), so load balancing from normal heavy sustained loads (though no load is 100% balanced) will have smaller, but repeated oscillations, probably reaching 1.4v often. These can and will very slowly degrade your processor.
The opposite also happens, when going from no load to heavy load or a lighter load to a heavier load. CPU requires amps, VRM's can't supply the amps fast enough as there is no vdroop cushion to give them time to do so, so the CPU voltage drops as much as 200mv (worst case!). So that 1.3v can become 1.1v for a few microseconds. What happens when this occurs? BSOD or crash.
Again that is worst case scenario. Apex Legends won't do this as it doesn't put a 150 amp load on you. However OTHER programs, like Realbench or Prime95 or Cinebench R20 can.
So you would not only find yourself possibly crashing/BSOD'ing when trying to run Realbench 2.56 or Cinebench R20 (and especially prime95 !!) at a bios voltage set to your normal minimum load voltage you need to be stable, but using Loadline Calibration level 8, but you would slowly degrade your chips from the spikes also.
Here is what worst case 0 mOhms loadline looks like on a scope:
Elmor did some tests with comparing the VMIN (minimum voltage required for stability) with LLC6 and LLC8, using a multimeter, to find the voltage that LLC6 was stable at under worst case scenario (FMA3 small FFT prime95) at LLC6 with vdroop, then setting the bios to that exact voltage and using LLC8 to match it at idle and load. The transients ruined his stability with LLC8.
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I fired up the my Maximus XI Gene + 9900K to see if I could replicate your behavior.
Core = 4.7G
Cache = 4.4G
P95 29.1 FMA3 Small FFTs 15K
LLC=6, Vcore set = 1.130V, Vcore read = 1.066V: 1 thread failed after 6 minutes
LLC=6, Vcore set = 1.140V, Vcore read = 1.074V: pass 20m+
LLC=8, Vcore set = 1.075V, Vcore read = 1.074V: 1 thread failed after 2 minutes
LLC=8, Vcore set = 1.085V, Vcore read = 1.083V: 1 thread failed after 4 minutes
LLC=8, Vcore set = 1.095V, Vcore read = 1.092V: 1 thread failed after 2 minutes
LLC=8, Vcore set = 1.105V, Vcore read = 1.101V: 1 thread failed after 9 minutes
LLC=8, Vcore set = 1.115V, Vcore read = 1.110V: 1 thread failed after 6 minutes
LLC=8, Vcore set = 1.125V, Vcore read = 1.119V: 1 thread failed after 2 minutes
LLC=8, Vcore set = 1.135V, Vcore read = 1.137V: pass 1h+
I repeated it again with LLC=6, Vcore set = 1.140V, Vcore read = 1.074V and 1 thread failed after 14 minutes. Probably 10-20mV extra would pass for 1h+.
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Basically, with LLC8, the transient dips ruined any benefit of using LLC8 with a lower bios voltage, compared to LLC6 with a higher bios voltage! So your load voltage (1.137v) was thus MUCH MUCH higher and thus much hotter (1.135v set, 1.137v read) than setting LLC6 wit 1.145v set and 1.080v read. But again this is 150 amps worst case load here.
Ok the point?
While your LLC8 is working in Apex Legends, you are putting your hardware at risk, long term. I would MUCH rather and would suggest that instead of using 1.30v LLC8, that you use 1.325v-1.35v LLC6. It's much safer for your CPU, and you will have lower temps than LLC8+1.30v and lower VRM temps also.
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