I have the GA35DX with the 2080 Ti GPU. It came with the card mounted vertically. Unfortunately, this leaves no room for any other PCIE card or for a 3080/3090. I've managed to remove the GPU to upgrade the M.2 SSD and PCIE WiFi card but I want to convert it to a regular horizontal mount directly to the motherboard. Is it possible to swap the PCIE holder on the rear? I believe there is a GA35 model with the 2070 that is standard mount so the back panel must exist somewhere. ASUS online support has not been helpful so far, just got a response that such a part is not available. My only other option is to strip out everything and mount into a new case.