Speed and memory
In our performance index the Arc A380 scores 9 and the GeForce GTX 1060 3GB scores 8, which makes the Arc A380 about 13% faster. That is a visible but modest gap, usually 5 to 10 fps in a game that runs at 60.
The Arc A380 has 6 GB of video memory and the GeForce GTX 1060 3GB has 3 GB. That difference matters at 1440p and in new games at High textures, and it can outweigh a small speed advantage as the card ages.
In our estimates for popular games at 1080p on High, the biggest gap is in Call of Duty (25 against 12 fps), and the smallest is in Fortnite (102 against 92 fps). Games that are light enough to run above 200 fps on both cards show little difference at all.