Quality | Scph90001biosv18usa230 Portable Extra
This specific, late-model motherboard (often dubbed a "90k" or "9000x" series) is highly coveted for portable builds because it features a very small, integrated motherboard, reducing the need for extensive trimming.
If you aren't building a physical handheld, this BIOS is often recommended for emulators like Compatibility scph90001biosv18usa230 portable