My GTX 1060 GPU doesn’t work on Blender 2.9 as OptiX I understand that the non RTX GPU has also been changed to use OptiX in this 2.9 update.
However, my GPU (GTX 1060) outputs a message when OptiX is selected that it will be rendered as a CPU and actually the rendering speed is slower than Cuda and the same as CPU. I rebooted the PC, but the result was still the same.
Am I misunderstanding this update?
The Nvidia GTX 1060 is supported for rendering with OptiX (see release notes), but it requires a current graphics driver. Updating it should allow you to select the GPU as OptiX render device for Cycles. The current drivers can be downloaded from Nvidia's website.