Seasonic aims to address one of the most persistent issues with modern high-end graphics cards, known as 12V-2×6 cable melting. To do so, the brand is embedding advanced monitoring and protection features on its next-gen Prime PSUs, meant to inform the user in case of atypical behaviour or outright shut the system down.
During Computex 2025, Seasonic showcased its upcoming enthusiast-grade PSUs, complete with some new and welcome innovations. The most notable one is undoubtedly OptiGuard, a potential solution to the 12V-2×6 connector issues. The idea is to precisely monitor both current and temperature of the 12V-2×6 connector on the PSU side, ensuring no wire is overloaded, which would subsequently risk melting the plastic housing.
As a reminder, modern graphics cards such as Nvidia’s latest RTX 50 Series tend to create unbalanced loads on the different 12V wires, overloading some more than others, which heats the cable due to a resistance increase. In the worst cases, where connections between the cable and GPU/PSU are not perfect, this could lead to hotspots that can melt the 12V-2×6 connector or cable.
Thus, to avoid leaving this unbalance unchecked, Seasonic is taking a proactive approach by monitoring the current going through each of the six 12V pins, all while measuring temperatures on each side of the connector (pins one and six). This data is then fed into a chip located inside the PSU, whose job is to detect the beginning of any symptoms before things get out of hand.
When detecting any deviation from safe operating thresholds, the PSU sends an alarm to inform the user. However, if this overload continues, then the PSU forces a shutdown, seemingly by cutting power completely. This approach effectively creates a closed-loop safety system, tackling both the symptom (overheating cables) and its root cause (uneven load distribution) in real time.
While this would ruin any ongoing task in addition to potentially losing or corrupting SSD/HDD data, it remains a preferable outcome compared to a melted graphics card. Thankfully, Seasonic is aware of such limitations and is planning a second version of its OptiGuard that connects the PSU to the motherboard, allowing it to initiate a smoother OS-controlled shutdown.
Even in its current state, many would gladly take the tradeoff, essentially when alternatives such as MSI’s colour 12V-2×6 pins are ineffective when the power overload kicks in. A Redditor just found this the hard way when their cable started burning. Though we don’t know the cause, be it user error or unbalanced power, it seems unlikely to be the owner’s fault since MSI’s colour-coded connector would make a bad installation obvious. Thankfully, the Redditor’s expensive RTX 5090 doesn’t look damaged.
Seasonic plans to start production of its enhanced Prime PSU series this year, with market availability scheduled for Q1 2026. As someone who leaves his PC unattended for long durations, I know which PSU to get whenever I upgrade to a 12V-2×6-powered GPU.
