As chipmakers unveil their next-gen platforms, users prepare to buy new systems including CPUs, GPUs, motherboards, memory, and yes, even power supplies. The change in PSUs is primarily a result of the higher power requirements of the upcoming graphics cards. For the same reason, ATX 3.0 and PCIe Gen 5 power supplies have been introduced alongside the 12VHPWR power connectors which are capable of delivering 600W of power per connector.
Up until now, you’d need two or even three 8-pin power connectors to run the higher-end GPUs such as the RTX 3080, 3080 Ti, 3090, and 3090 Ti. However, a single 12-pin power connector is sufficient to power even the most demanding graphics cards, significantly simplifying cable design and density.
Many vendors have been pairing existing ATX 2.0 power supplies with the 12-pin “12VHPWR” power connector, but the PC-SIG has warned of negative consequences as a result. The 12VHPWR power connector is designed to sustain a load of up to 600W safely while each 8-pin connector tops out at 150W. Anything higher is a safety risk.
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. Although PCI-SIG specifications provide necessary information for interoperability, they do not attempt to encompass all aspects of proper design, relying on numerous industry best-known methods and standard design practices. As the PCI-SIG workgroups include many knowledgeable experts in the field of connector and system design, they will be looking at the information available about this industry issue and assisting in any resolution to whatever extent is appropriate.
As more details emerge, PCI-SIG may provide further updates. In the meantime, we recommend members work closely with their connector vendors and exercise due diligence in using high-power connections, particularly where safety concerns may exist.
Thank You,Source: WCCFTech
Testing by WCCFTech reveals the following:
12VHPWR Connector To 2 x 8-Pin Adapter In 600W Test Load:
- 1 x 8-Pin Connector = 25.4A or 304.8W (2x Increase Over 150W Rating)
- 1 x 8-Pin Connector = 25.1A or 301.2W (2x Increase Over 150W Rating)
12VHPWR Connector To 3 x 8-Pin Adapter In 450W Test Load:
- 1 x 8-Pin Connector = 25.34A or 282.4W (88% Increase Over 150W Rating)
- 1 x 8-Pin Connector = 7.9A or 94.8W (Within 150W Power Rating)
- 1 x 8-Pin Connector = 6.41 or 76.92W (Within 150W Power Rating)
As you can see, connecting a 12VHPWR connector to two or three 8-pin connectors results in one or more connectors, bypassing the safe limits by a large margin.