At their core, the ASRock B850 Steel Legend WiFi and the ASRock B850M Steel Legend WiFi are nearly identical in terms of platform and features: both use the AM5 socket with a B850 chipset, support the full Wi-Fi 7 (802.11be) stack down to Wi-Fi 4, pack Bluetooth 5.4 for low-latency wireless peripherals, output video via HDMI 2.1, and share the same overclocking support, dual BIOS safety net, RGB lighting, and a solid 3-year warranty. For the vast majority of general-use considerations, these two boards are functionally twins.
The one meaningful distinction in this group is form factor. The Steel Legend WiFi is a full ATX board measuring 305 × 244 mm, while the Steel Legend M is Micro-ATX at a more compact 244 × 244 mm. In practice, this means the ATX variant requires a mid-tower or larger case and typically offers more physical space for expansion slots, VRM cooling headroom, and cable management — even if the chipset-level feature set is shared. The Micro-ATX model, by contrast, fits smaller cases and is better suited to compact or space-constrained builds without sacrificing the platform's core capabilities.
Neither board has a clear overall advantage here — the choice comes down entirely to your case and build goals. If you are planning a full-sized desktop with room to grow, the ATX model has the edge in physical flexibility. If a smaller footprint is a priority, the Micro-ATX delivers the same platform in a tighter package with no feature penalty based on the specs in this group.
