mpac

4 pin. yea maybe under load fan voltage sags. I should try splitting the power out to the motherboard and keep signal and tacho signals to the card.

the fans on the gpu work fine elsewhere. even on the gpu they work fine until high gpu load.

like I said, it doesn't matter. even if set to one constant speed. as you can see in the image, temp and fan speed is constant, yet fan rpm is fluctuating.

between 2 PCs, 5 cards tested, all exhibit the exact same behavior. 3 were from one retailer, 2 were from a completely different retailer. when under load (>90%) the fan rpm keeps dropping and sometimes spike to 3500rpm. even if set to manual fan mode,doesnt matter which speed I set it to, fans will run fine until I give it a load >90% such as playing a game. doesn't happen when doing desktop work, or even running realbench regardless which speed I set it to. gaming/graphics benchmarks only. tried latest and past drivers. tried setting custom fan curves, manual fan settings all speeds, doesn't make a difference. the sound is annoying with it constantly revving during gaming. just curious what it could be? it'll run for 5-10 seconds, then starts getting these spikes and drops, and it keeps repeating.