PCI-SIG Warns of Potential Overcurrent/Overpower Risk With 12VHPWR Connectors

With next-gen approaching launch soon, one of the main components that users would want to update for their PCs is their PSU. This is due to new requirements and standards that have been set in place to deliver sustained and clean power, avoiding any issues in regard to transient spikes and power excursions. While there are many manufacturers who are bundling Gen 5 (12VHPWR)  connectors with their existing PSUs, here’s why it is a much better choice to invest in a real ATX 3.0 compliant PSU.

Here’s Why You Should Be Getting An ATX 3.0 Compliant PSU With Proper Gen 5 (12VHPWR) Connectors

PSU manufacturers are getting ready for a grand launch of their new ATX 3.0 designs but there are also certain manufacturers who are bundling their existing ATX 2.0 PSUs with Gen 5 connectors. As expected, upcoming graphics cards are going to be really power-hungry and would require up to 600 Watts of power.

What Is The 12VHPWR Connector?

The 12VHPWR Auxiliary Power connector is designed to deliver up to 600 watts directly to a PCIe* Add-in Cards. This power connector is not compatible with the existing 2×3 or 2×4 auxiliary power connectors. The 12VHPWR connector power pins have a 3.0 mm spacing while the contacts in a 2×3 and 2×1 connector are on a larger 4.2 mm pitch. The 12VHPWR auxiliary power connector includes twelve large contacts to carry the power and four smaller contacts beneath carrying the sideband signals.

ATX 3.0 12VHPWR Connector Specs

The connector performance requirements are as follows:

• Power Pin Current Rating: (Excluding sideband contacts) 9.2 A per pin/position with a limit of a 30 °C T-Rise above ambient temperature conditions at =12 VDC with all twelve contacts energized. The connector body must display a label or embossed H+ character to indicate support of 9.2 A/pin or greater. Refer to the approximate positioning of the marker on the 12VHPWR Right Angle (R/A) PCB Header.

ATX 3.0 Gen 5 vs ATX 2.0 Gen 5, What’s The Difference?

To hit their 600W power requirement, the graphics cards will be outfitted with either a single PCIe Gen 5 (12VHPWR) connector or three 8-pin connectors. If you are using an existing ATX 2.0 PSU, the only option you have is to either use a Gen 5 adapter or three 8-pin connectors to boot your card. In the case of an ATX 3.0 PSU with a Gen 5 plug coming from the main unit, you don’t have to worry about any adapters since that would be a direct connection from the PSU to the graphics card.

Now most manufacturers have told that using a standard 8-pin to 12VHPWR adapter should work just fine but according to PCI-SIG, that’s not the case. As you see, the 12VHPWR Gen 5 connector is designed to sustain a load of up to 600W while a 8-pin connector is designed to sustain a max load of 150W. And here’s where the safety risk arises.

Following is the mail forwarded PCI-SIG on the safety risks associated with using non-ATX 3.0 compliant  Gen 5 PSUs:

Dear PCI-SIG Member,

Please be advised that PCI-SIG has become aware that some implementations of the 12VHPWR connectors and assemblies have demonstrated thermal variance, which could result in safety issues under certain conditions….