I currently have my Z370 Auros Gaming 7 paired with my 9900k @ 5.0ghz (requires 1.38v yuk!) and have also noticed the VRM on this board gets aggressively hot if the CPU is absolutely pinned for 15-20+ mins and will eventually start downclocking due to VRM temps 100c+. Normal use this is never an issue and I will typically see 70-80c on the VRM near the CPU using my laser thermometer. What's weird is that I have never heard the internal VRM fan spin up and supposedly it's relatively loud what with it being so small and having high RPM.
I have considered adding an additional fan downwards to blow onto the block/VRM but aesthetically it's just not gonna happen for me. Same goes for adding additional blocks to the VRM, I kinda like the way the heatsinks look now with the velocity block. I *may* go so far as to change out the thermal pads for some kryonaut or something similar, I have even contemplated getting or having a little 'vent' made to put on top of the rear fan (to be used as an intake) which would have baffles that divert the air towards the CPU/VRM instead of straight into the case thusly allowing for increased cooling in this area as well as not directly pushing against the air coming in from the top fans on the front radiator (and honestly even this is fine since the air gets sucked out by the top radiator relatively agressively).
Gigabyte Z370 Gaming 7
EVGA RTX 2080 Ti XC ULTRA
Kingston HyperX Predator RGB
ADATA XPG SX8200
EVGA SUPERNOVA G2
EK Velocity Nickel-Plexi, EK Vector RTX Nickel-Plexi, EK EX360, Koolance 360mm, Enermax Neochanger
Logitech G502 Spectrum
Audiotechnica ATH-900X, SBX G5, MODMIC
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