Folks, I'm running a ROG Strix 1080Ti (this one - https://www.asus.com/uk/Graphics-Cards/ROG-STRIX-GTX1080TI-O11G-GAMING/) with a 600W PSU in a mini itx case. The card *just* fits (length is okay, but width means there is very little clearance on the underside of the card to the PSU shroud (Nzxt H210 case). Assuming I want a RTX3080, I think I can straight swap and the sizes will be similar (or the 3080 might be a tiny bit smaller??)