Hello there,
I can not give detailed instructions, but want to share an interesting thing on Comfyui using the portable version, moving from a GTX108ti to a RTX3080.
I simply copied the whole install folder on the new machine, renders performed 5-10 times faster as on the 1080ti. Then after “updating” cuda (IIRC torch Cuda) i experienced a huge performance loss even using the newest Nvida drivers. Grok said the 3080 could deal way better with a lower cuda because of certain “driver fallbacks”. So if you experience bad performance on your 3080 you may gain performance by downgrading to a lower cuda thats rather for a 1080 then a 3080.