Despite sticking with PCI-Express Gen 4 as its host interface, the NVIDIA GeForce RTX 4090 "Ada" graphics card standardizes the new 12+4 pin ATX 12VHPWR power connector, even across custom-designs by NVIDIA's add-in card (AIC) partners. This tiny connector is capable of delivering 600 W of power continuously, and briefly take 200% excursions (spikes). Normally, it should make your life easier as it condenses multiple 8-pin PCIe power connectors into one neat little connector; but in reality the connector is proving to be quite impractical. For starters, most custom RTX 4090 graphics cards have their PCBs being only two-thirds of the actual card length, which puts the power connector closer to the middle of the graphics card, making it aesthetically unappealing, but then there's a bigger problem, as uncovered by Buildzoid of Actually Hardcore Overclocking, an expert with PC hardware power-delivery designs.

CableMod, a company that specializes in custom modular-PSU cables targeting the case-modding community and PC enthusiasts, has designed a custom 12VHPWR cable that plugs into multiple 12 V output points on a modular PSU, converting them to a 16-pin 12VHPWR. It comes with a pretty exhaustive set of dos and don'ts; the latter are more relevant: apparently, you should not try to arm-wrestle with an 12VHPWR connector: do not attempt to bend the cable horizontally or vertically close to the connector, but leave a distance of at least 3.5 cm (1.37-inch). This ensures reduced pressure on the contacts in the connector. Combine this with the already tall RTX 4090 graphics cards, and you have yourself a power connector that's impractical for most standard-width mid-tower cases (chassis), with no room for cable-management. Attempting to "wrestle" with the connector, and somehow bending it to your desired shape, will cause improper contacts, which pose a fire-hazard.