Just activate the other machine. It will give you the option to clear the other activation. Just make sure the GPU is enabled in the PS prefs for the new computer. This issue you are having is for certain the GPU being turned off. However, that isn’t to say for certain there are not any other PSD setup issues or something you may see after getting the GPU working. Just need to get the GPU working first though and then see if the PSD setup is correct and it all runs fine after that.