SteamVR overdrive & Nvidia Single Pass Rendering

SteamVR overdrive states a pixel resolution per eye according to the choosen percentage (e.g. 2500x1700 with 150% instead maybe 1600x1440 with 100% … just numbers). But that if i set single pass rendering only one frame is rendered according to Nvidia. But what resolution is active then? Both eyes within one frame (eg. 5000x3400 according to the example above) or just one frame with 2500x1700?

Has somebody an idea how this works together?

Kind regards