Gigabyte RTX 4060 boards investigated for VRM fault linked to PCB burnouts
© Paulo Gomes Brazilian graphics card repair specialists Paulo Gomes and SidNelson have documented recurring short-circuit failures on Gigabyte GeForce RTX 4060 boards, with the investigation focusing on the AERO model. The damaged cards show severe PCB carbonization close to the HDMI output. The technicians argue that the damage begins inside the GPU power circuit rather than through the display connector.
The team examined damaged boards alongside a sealed and functional Gigabyte sample. An Inno3D RTX 4060 was also used for comparison. Measurements were performed with an oscilloscope and multimeter to examine the four phases supplying power to the GPU.
GPU power phases show inconsistent behavior
© Paulo Gomes 
© Paulo Gomes A multi-phase VRM divides the GPU load between several parallel power stages. The phases are intentionally offset from each other, but they should operate at similar switching frequencies and duty cycles when supplying the same voltage rail. This allows the controller to distribute current without placing most of the load on one set of MOSFETs.
All four GPU phases on the Inno3D board produced closely matched waveforms at approximately 207 kHz. The Gigabyte board produced much larger differences between phases. In the original configuration, the technicians observed one phase moving between roughly 150 and 300 kHz while other phases behaved differently under the same conditions
© Paulo Gomes By analyzing sealed and damaged boards with an oscilloscope and multimeter, we identified:
- VRM phase imbalance: Gigabyte’s current-control circuit (Current Sense/PWM) has a sizing error in resistors/capacitors.
- Irregular behavior: each power phase operates with completely unregulated frequencies and duty cycles relative to one another, overloading specific MOSFETs.
- Result: the MOSFET shorts out, collapses, and carbonizes the PCB right in the area near the video output, (falsely) simulating a spike coming from the HDMI port.
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The Repair and Solution
We emphasize that this failure is a hidden defect (a manufacturer design flaw), not customer misuse. We call on Gigabyte to take a stance (warranty or recall) and recommend that affected users pursue their rights under Brazil’s Consumer Protection Code. At the end of the video, yet another customer arrives at the shop with exactly the same problem, confirming how recurrent this defect is.
— Paulo Gomes to VideoCardz
The suspected source is the current-sense network connected to the PWM controller. This circuit reports the current passing through each phase so that the controller can balance the load. Gomes and SidNelson found different resistor and capacitor configurations across the four feedback paths. They believe this causes the controller to distribute current unevenly, overloading one MOSFET until it shorts and carbonizes the PCB.
The failed power stage is located close to the video outputs. Once the MOSFET collapses, the resulting heat and current can burn the board in the direction of the HDMI connector. The resulting damage resembles an external surge entering through HDMI, which the technicians say has led to some warranty claims being rejected as customer misuse.
Damaged board repaired with three VRM phases
SidNelson removed the original current-sense components and rebuilt the feedback circuit using working graphics card designs as references. One phase on a badly carbonized board could not be restored, so it was disabled. The remaining three phases received higher-rated MOSFETs, damaged traces were reconstructed and a fuse was added to the 12V input.
Oscilloscope measurements after the modification showed much closer switching behavior across the remaining phases. The card restored its video output and completed stress testing.
The investigation does not establish how many cards are affected or confirm that every Gigabyte RTX 4060 revision uses the same configuration. The tested boards carried several 2023 production markings, and another card with similar carbonization arrived while the video was being completed.
The technicians have asked Gigabyte to explain the component choices and review warranty claims involving the same failure pattern.
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