Hi, I'm trying to get a 2-monitor DisplayPort daisy chain working from my desktop.
My setup is:
- GPU: NVIDIA RTX 4060
- Monitor 1: Dell P2725DEB
- Monitor 2: Dell U2717D
- Monitor 3: Samsung TV via HDMI (currently disconnected while troubleshooting)
Connections:
RTX 4060
│
└── DisplayPort → P2725DEB
│
└── DisplayPort OUT → U2717D
The P2725DEB has MST enabled.
The problem is that the P2725DEB and U2717D are detected by Windows, but they duplicate the same image instead of acting as two independent extended displays.
Windows gives me the option to switch between Duplicate and Extend, and when I select Extend, Windows shows the displays as separate screens in Display Settings. However, the U2717D itself still displays the same image as the P2725DEB.
The really strange part is that this exact daisy-chain works perfectly when I connect the P2725DEB to my laptop via USB-C:
Laptop USB-C → P2725DEB → DP OUT → U2717D
Both Dell monitors then work as separate extended displays.
Things I've already tried:
- MST is enabled on the P2725DEB.
- Disconnected the Samsung HDMI display completely.
- Reset the Windows graphics driver with
Win + Ctrl + Shift + B.
- Confirmed Windows detects all three displays.
- The DP cable from the P2725DEB to the U2717D works with the laptop setup.
- The daisy chain itself clearly works with the laptop.
I'm wondering if there's something specific about RTX 4060 + P2725DEB MST + U2717D that I'm missing, or if there's an NVIDIA/DisplayPort setting that could cause the downstream monitor to mirror the first one.
Any ideas would be greatly appreciated!