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Why Doesn’t My Monitor Work Properly with a 66W USB-A Fast Charger?Updated 7 minutes ago

If your UPERFECT monitor doesn' t power on or function properly with a 66W USB-A fast charger, the issue lies in the charging protocol, not the wattage. You might have questions about this, and we'll explain the details in this article.

Why USB-A Fast Charging Doesn't WorkHUAWEI super charge 66W

  • Different protocols: USB-A fast chargers (like QC or SCP) are designed for phones and small devices. They use proprietary charging methods, not the universal USB Power Delivery (PD) standard.
  • Fixed 5V output: Without PD negotiation, a USB-A port usually only delivers 5V. Even if the charger is rated at 66W, your monitor may only get about 15W.
  • No PD handshake: UPERFECT monitors require PD communication to activate normal working mode. Since USB-A lacks the PD handshake, the monitor can't recognize it as a valid power source.
  • Connector limitation: PD works only through USB-C. The USB-A port physically cannot carry the PD signal.

USB-C Plug Pinout (Supports PD Protocol)

USB-A Plug Pinout (Does Not Support PD Protocol)

What Your Monitor Actually Needs

  • Protocol + power: The monitor needs both enough wattage and the correct PD protocol.
  • Minimum requirement: At least 15W (5V/3A) is needed when the monitor is handling both video and power through the same cable.
  • Recommended headroom: A 30W (or higher) USB-C PD charger ensures stable operation and leaves room for extra features.

How to Fix the Issue

  1. Use a USB-C PD charger. Look for one rated at 30W or more.
  2. Connect with a USB-C to USB-C cable. Avoid USB-A to USB-C cables. They can't transmit PD.
  3. Check the power profile. A proper PD charger will negotiate the right voltage (such as 9V, 15V, or 20V) for your monitor.
  4. Restart the monitor. After switching to PD power, the screen should turn on normally.
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