For people that are wondering about the "Meltdown" security patch performance decrease on their mining rigs on Windows 10
From the one miner that i have which is running Intel G4400 and 8 GPUs (1x 980ti, 7x 1060 3GB).

The performance on 0.5.8 before the patch = 2597 h/s
Performance after Meltdown security patch = 2565 h/s

So about 1.23% decrease in hashrate.