I have a few videos I have come across that talk about converting a server power supply for other uses. I’m including them here.
BONUS 3: Page on converting a power supply on ArcadeEd’s page: https://arcaded.discussion.community/post/server-power-supply-mod-8171641
HP DPS-600PB Power Supply – DPS 600 based:
HP DPS460BB Power Supply DPS 460 based:
Another HP Server power supply:
These should get you started. Dell has a similar setup. These are some good videos to get you started, with a few links to learn a bit more about converting power supplies.