[SOLVED] What are the -12V and -5V supply rails used for?

[ziptol]

Just curious.

 

[Barty1884]

-5V has been optional since about 2003..... nothing modern uses it.
Historically I believe it was motherboards and expansion cards (pre PCI or AGP) that typically used -5V

-12V is dated, but still in the ATX spec.
Historically, serial ports and some sound cards, I think?
-12V is also still a requirement for PCI which, while not particularly 'common', are still present.

 

[lumineZ]

3.3 volts and 5 Volts towards a USB drives, HDD or SSDs.

Read more here if you want since there is might be some changes comming when it comes to the PSU`s.
https://www.guru3d.com/news-story/a...24-pins-atx-connector-anymorebut-10-pins.html

 

[jonnyguru]

Just curious.

Nothing. Absolutely nothing.