Modders have rebuilt a Galax GeForce RTX 5090D HOF OC LAB XOC to use three traditional 8-pin PCIe power connectors instead of its original dual 16-pin arrangement. The experimental card reportedly exceeded 900 watts, reached 3,400 MHz, and remained operational during extended testing—renewing debate over high-power GPU connector designs.
Key takeaways
- TecLab replaced the card’s dual 16-pin inputs with three soldered 8-pin connectors.
- The modified RTX 5090 reached roughly 900 watts, 120 amps, and 3,400 MHz.
- Two connectors supported about 3,200 MHz, while one reached approximately 3,100 MHz.
- The experiment does not make the modification safe or practical for ordinary PC builds.
The results are notable for PC builders because the RTX 5090 carries a 575-watt TDP and relies on the compact 12VHPWR-derived 12V-2×6 connector. TecLab’s demonstration suggests that a properly distributed power delivery system can handle extreme loads, although it does not represent a retail graphics card design.
How the RTX 5090 was modified
The Brazilian TecLab team started with Galax’s flagship RTX 5090D HOF OC LAB XOC, a heavily built card originally equipped with two 16-pin connectors. After removing the original power hardware, the modders installed three 8-pin Mini-Fit Jr. connectors directly on the PCB using hand-cut copper plates and heavy-gauge wiring.
They also rewired the sense-pin configuration so the card would recognize the replacement power arrangement and permit higher power limits. The changes were made at the hardware level; reports indicate that no modified BIOS or firmware was required. A custom liquid-cooling setup handled the GPU’s thermal output.
Extreme power and clock-speed testing
During roughly an hour of testing, power levels were increased from about 400 watts to more than 900 watts. At its peak, the card reportedly pulled close to 120 amps while running at 3,400 MHz. Connector and cable temperatures remained comparatively low in the three-connector configuration, with reported temperatures around 35°C.
TecLab also tested fewer power connections. Two 8-pin connectors supported approximately 66 amps and a clock speed near 3,200 MHz. With only one connector, the card still reached about 3,100 MHz, although the cable temperature rose to roughly 65°C in one report. PC Gamer additionally reported a test exceeding 3,300 MHz with two connectors in Port Royal.
What the experiment actually proves
The demonstration indicates that the physical conductors and contacts in an 8-pin system may have more capability than the official 150-watt GPU-side specification suggests, particularly when power is spread across multiple connectors and carefully monitored. It also highlights why enthusiasts remain concerned about concentrated current and contact resistance in compact 16-pin designs.
However, the modified card used premium hardware, direct soldering, custom cooling, and controlled testing. A three-8-pin arrangement is officially associated with roughly 450 watts of GPU-side capacity, so TecLab’s 900-watt result substantially exceeds normal specifications. It should not be treated as a recommendation for modifying a retail card, power supply, or cable.
For ThinkComputers readers evaluating future GPUs, the practical takeaway is caution rather than a do-it-yourself upgrade path. Connector reliability, cable quality, load balancing, installation, and cooling all matter—and Nvidia or board partners would need to validate any alternative design across thousands of cards before it could replace 12V-2×6 in commercial products.