Take A Load Of The PSU, You Put The Load Right On The Motherboard
Intel’s ATX12VO is an initiative to change PSUs to provide one single 12V rail, with any other needed voltages generated using step-down converters on the motherboard. While this may seem odd, it is worth recalling that the good ol’ ATX standard was developed by Intel back in 1995, so they do have a right to go nosing around PSU development. We’ve also seen the removal of the -5V rail from the ATX 2.0 spec as well as the -12V rail becoming optional, so the tradition of simplifying power delivery does have precedent.
There are systems such as Dell’s G5 5000 which already make use of their own 12V only. Those who have dealt with the internal power supply of a Dell machine may now start to see the benefit of a standard applied across pre-built models, perhaps not for DIY machines though. The drawback is that ATX12VO would make PSU design somewhat easier and increase power efficiency as well, but it also pushes the onus of providing any other voltages onto the motherboard. This means more expensive motherboards as well as yet another point of failure. As a PSU is both less expensive and longer living than your average motherboard; which makes this idea less attractive for those that build systems on their own as opposed to buying boutique.
Hackaday takes a look at this proposal, the reasons behind it and the history of the ATX spec in this post, if you’d like to learn more about Intel’s plans for the PSU.