From previous rumors, we know that NVIDIA’s next-gen Ada Lovelace flagship, the RTX 4090 will be a major upgrade over the RTX 3090. This is going to come at the cost of power. Various reports have indicated a power draw of up to 600W. This will be facilitated by the new 12VHPWR power connector. As part of the next-gen PCIe Gen 5 standard, the PCI SIG has defined a new “High Power Connector” or H+ for graphics cards with a power requirement of up to 600W. The 12VHPWR connector is a major departure from the existing PCI Express 2×3/2×4 Auxiliary Power connectors. While the pins of the former have a spacing of 3.0 mm, the latter has a larger spacing of 4.2 mm. Therefore, they won’t be compatible with the same hardware and require changes on both the PSU and the GPU PCB.
The 12VHPWR power connector can supply up to 55A of continuous power to the graphics card via its 12V power rail with a maximum power of 600W. The PCI SIG specifies a pin current capability (excluding sideband contacts) of 9.2 A per pin/position with a limit of 30 °C T-rise above ambient temperature at + 12 VDC with all twelve contacts energized. This results in 55.2 amps in one direction for the 12-volt power rail or 662.4 watts. Taking the tolerances and safety precautions into place, up to 600W of power can be safely supplied to the add-in board (a reduction of 11% over the max possible). The added power consumption may seem like a step back for GPUs, but the new connector will simplify plug and PCB design quite significantly. NVIDIA’s RTX 40 series graphics cards, most notably the RTX 4080 and 4090 should leverage this new power connector along with support for PCIe Gen 5.
However, according to a Tweet from @TtLexington, the GeForce RTX 4090 may have a TGP exceeding 700W. While this isn’t entirely out of question, it’s a bit hard to believe, especially when you consider that the 12VHPWR power connector can only supply a maximum of 600W safely. It’s possible that NVIDIA will go opt for a custom connector with more rails or something else entirely.
Either way, it looks like the higher-end Ada Lovelace parts including the GeForce RTX 4080 and 4090 will be serious power hogs, requiring a lot of users to switch to a higher-end power supply. The newer CPU socket and memory mean that everything right from the motherboard to the PSU will have to be swapped out.
