Intel updates power spec over melting 12VHPWR plugs, but existing PSUs are fine

An Intel update to the ATX power supply spec doesn’t mean your current 12VHPWR adapter or PSU is obsolete or dangerous. The ATX 3.01 update, published last month by Intel, recommends that PSU vendors building 12VHPWR connectors use “spring” connections rather than “dimple” connections.

“Crimp Contacts inside of the cable plug are recommended to use the 4 Spring design instead of 3 dimple design (as shown in below figure) which will increase the contact area for electrical current flow inside the 12VHPWR connector and reduce the temperature rise of each contact,” the updated ATX 3.01 spec reads.

Reading between the lines of it, it’s clear one is better, but does that mean existing dimple connectors need to be replaced?

“No,” Intel Platform Power Specialist Stephen Eastman told PCWorld. “Using an existing 12VHPWR connector can work well when implemented and installed correctly.”

Eastman recommended that people view Nvidia’s website post on properly inserting a 12HVPWR power connector into a GPU.

“The new four spring design does have extra reliability benefits, but that does not mean the existing three dimple design is bad,” Eastman said. Intel decided to adopt the recommendation after connection vendors shared information showing the four-spring design to offer more surface contact, lower temperatures as well as better durability.

The world would not be so focused on tiny metal connections inside of a power connector except for the five-alarm fire of concern last year after dozens of 12VHPWR cables started to melt, sometimes damaging the $1,500 graphics cards they were powering. At one point, attention focused on the type of connections after a report by Igorslab.de said the spring clips appeared to be superior to the dimple clips.

After weeks of hand-wringing and speculation though, the cause of those melted cables likely traced back to the cables either backing out or not being fully inserted, according to an investigation by Stephen Burke of Gamers Nexus. Nvidia later concurred and said of the 50 reports of damaged connectors it received, all likely were the result of power cables that weren’t fully inserted. Many of the pictures of melted cables posted on Reddit and Twitter also showed melt lines indicative of a cable that had backed out or had not been inserted fully.

Despite installation likely being the cause of the problems, Intel’s update indicates room for improvement to the connector—but not enough to mandate it. The new ATX 3.01 spec, in fact, “recommends” the four spring connection but does not require them, which means a power supply vendor can continue to manufacture and sell units with the dimpled connectors.

Eastman said in indication of how minor this update to the spec is, he doesn’t think PSU vendors will bother to note it on boxes and Intel’s own test procedures on PSUs won’t even change for it.

So why even bother to update the spec if the older one is fine?

Eastman said publishing it as part of the spec helps “to make sure PSU vendors know there are options—it has worked as some PSU vendors have started to explore all the options.”

The update for the 12VHPWR itself is part of other tweaks to the spec to clean up language and make changes such as no longer requiring that a power supply vendor put the wattage of a 12VHWPR on the cable itself. That change was made due to fully modular cables where a cable might be used in different models power supplies so labeling would be used on the PSU body rather than the cable.

And despite some thinking the spec means a new connector, Eastman stresses that it is not a new connector at all.

“This shows some options that PSU vendors can look at for options as they design PSUs with 12VHPWR connectors,” he said.

The updated spec also appears to bring the ATX spec in line with the PCI-SIG’s spec change introduced in January. The PCI-SIG engineering change notice introduced two different 12VHWPR connectors for use.

Despite Intel’s public presence with the ATX spec and its introduction of 12VHPWR, the company doesn’t own the spec.

“We understand that PCI-SIG documents are not as readily available to the public and the ATX spec is the default Public document,” Eastman said. “But Intel did not create, define, or own the 12VHPWR connector. Intel is one of many members that make up the PCI-SIG that created, defined, and owns the 12VHPWR connector.”