The latest Power Supply Design Guide has been updated to recommend only one type of cable plug for graphics cards. For 12VHPWR connectors, which can provide up to 600W of power to a single GPU, it is now recommended to use a plug design called 4 Spring to reduce the risk of temperature rise.

The 12VHPWR connector is a fairly new concept in the PSU world, first introduced in early 2022 as part of the redesign of the ATX 3.0 specification (opens in new tab) The ATX 3.0 specification is essentially a modern PSU for manufacturers issued by Intel a how-to guide for building them, and ultimately determines how the various connectors and standards will actually be brought to market.

In a recent update to the ATX 3.0 PSU specification found by Twitter user harakaze5719 (opens in new tab), Intel now recommends only one design known as 4 Spring for 12VHPWR connectors and 3 Dimple for They are actively discouraging manufacturers from using alternative connectors.

And Intel has provided a handy image (from Wieson* Technologies Co.) showing the actual difference between a dimple and a spring plug

This seemingly minute design change is of interest because the GPU of Nvidia's high-end RTX 40 series graphics cards The exact design of these two connectors has been called into question by instances of connector (opens in new tab) melting; AMD's latest graphics cards do not use the 12VHPWR connector (opens in new tab).

A November Igor's Lab report on this issue (opens in new tab) points out that Nvidia has two suppliers of 12VHPWR adapters, with a company called NTK producing a 4-spring design and Astron producing a 3-dimple design Igor's Lab, in this same article, published an Nvidia slide highlighting these two conflicting designs, noting that the NTK design (opens in new tab) appears to be the more robust connector overall.

Igor's Lab did not lay all the blame for the reports of power connectors melting solely on these differences in the power plugs on the connectors. However, they attributed some of the problems with the 12VHPWR connectors to the less than ideal 3-dimple design.

In a customer support update, Nvidia officially attributed the glitch (opens in new tab) to an improper connection, noting that users should absolutely make sure that the 12VHPWR connector is fully plugged into the graphics card.

Improper contact appears to be the problem. Regardless of whether the plug is poorly designed or the connector is improperly plugged in.

Officially changing the ATX 3.0 specification is a step in the right direction to address this problem once and for all. It is important to note, however, that Intel did not actually design the 12VHPWR connector. This is specified in the PCIe 5.0 specification, which means that changing the connector is the work of the PCI-SIG (a special interest group made up of hundreds of global high-tech companies).

Last year, the PCI-SIG washed its hands of the issue (opens in new tab) after filing a class action lawsuit against Nvidia over the connector melting, noting in a statement sent to PC Gamer: "Members are concerned that the PCI-SIG specification does not provide the interoperability When implementing the PCI-SIG specifications, members are responsible for the design, manufacture, and testing (including safety testing) of their products. The member is responsible for the design, manufacture, and testing (including safety testing) of the product. "

PCI-SIG has made changes to the 12VHPWR specification, but the only significant change to the connector listed so far on the PCI-SIG specification page (opens in new tab) is with respect to the four sense pins that run along the bottom of the 12-pin power connector, not the actual power pins not the actual power pins. Over time, further changes to this specification are likely to be made.