HP Laptop ProBook Intel Core i3 1st Gen 380M (2.53GHz) 2GB Memory 320GB HDD Intel HD Graphics 15.6" Windows 7 Professional 32-bit 4520s (XT989UT#ABA) - Newegg.com
HP ProBook 4520s SSD and Ram Upgrade 2021 - YouTube
HP ProBook 4520s Optical Drive Replacement - iFixit Repair Guide
Just got my Mother's old work laptop. ProBook 4520s, i5 M460. Surprisingly, it games quite well! Thoughts/Suggestions? : r/laptops
HP ProBook 4520S HDD SSD Caddy
Amazon.com: New 2nd HDD SSD Hard Drive Caddy for HP ProBook 4530s 4540s 4520s 4430s 4510s 4515s 4320s 4540s 4545s Laptop Computer, SATA3 Second Solid State Drive Enclosure, Optical Bay Adapter Replacement :
HP ProBook 4520S - How To Replace Hard Disk Drive HDD or SSD - YouTube