You cannot boot Windows 10 from Port 4 or 5. If your SSD is in Port 4, the BIOS will not recognize it as a boot device. This is a critical detail missing from old forum posts.
Many scanned copies online are low-resolution, not OCR'd, and have handwritten service notes from 2016. Even "new" digital copies from HP's support site are clunky PDFs with broken internal links. hp ms7860 ver 12 motherboard manual new