Visually, the ASUS ROG Zenith II Extreme is recognized by its striking covers and RGB LED lighting. The illumination, adjustable via the manufacturer's software, is located on the cover of the I/O panel, the active chipset cooler, and on the right rear side of the PCB. For additional RGB components like fans and LED strips, the TRX40 mainboard offers several RGB headers: two 3-pin for digitally addressable RGBs and two 4-pin for conventional RGBs.

Other important features of the ASUS ROG Zenith II Extreme include a WLAN/BT module (Intel WiFi 6 AX200) and a LAN port with 10 Gbit/s (Aquantia AQtion AQC-107), supplemented by a Gigabit LAN port (Intel I211-AT). For audio, the manufacturer uses the ROG SupremeFX S1220 Audio Codec with ESS SABRE 9018Q2C digital-to-analog converter, providing a total of five illuminated 3.5 mm jack sockets and an optical S/PDIF output at the I/O panel.

The mainboard has a USB 3.2 port (USB 3.2 Gen 2x2), which comes in the form of a USB type C socket and reaches a maximum data transfer rate of 20 Gbit/s. The I/O panel also features seven USB 3.1 ports—one type C port and six type A ports—along with four USB 3.0 ports with type A connectors. USB 3.1 or USB 3.2 Gen 2 reaches maximum speeds of 10 Gbit/s, while USB 3.0 or USB 3.2 Gen 1 reaches a maximum of 5 Gbit/s per port.

Internally, the mainboard offers two USB 3.1 type C connectors (one header each) for modern PC cases, along with four USB 3.0 ports (two headers) and three USB 2.0 ports (two headers).

The E-ATX mainboard provides four PCIe x16 slots in the 4.0 standard for plug-in and expansion cards. It includes eight SATA 6G ports (with RAID support) and two M.2 slots, each with four PCI Express 4.0 lanes directly connected to the CPU. It supports the advanced NVM Express protocol, optimized for highly parallel disk access of modern PCIe SSDs.