What's going on

DisplayPort relies on a active communication protocol between your PC's graphics card and the monitor's scalar board. Unlike HDMI, which uses continuous passive detection, DisplayPort uses a signal called Hot Plug Detect (HPD) to tell your computer when a display is connected and ready to receive pixels.

HP monitors—especially modern E-Series, OMEN, and Pavilion lines—frequently lock up their internal scalar logic when power-saving states clash with modern GPU low-power modes. When the DisplayPort handshake drops for even a millisecond, the monitor may give up on searching for a signal entirely, displaying a "No DisplayPort Signal" message before dropping into deep sleep.

Symptoms people notice

• The monitor displays "No DisplayPort Signal" or "Active Signal Not Detected" and immediately goes to standby.
• The display turns on during system boot (showing the motherboard BIOS splash screen) but goes pitch black once Windows loads.
• Connecting via HDMI displays your desktop perfectly, but plugging in DisplayPort results in a black screen.
• The computer plays a device disconnect sound every time the HP monitor enters sleep mode.
• Display settings show a second monitor attached, but the screen refuses to illuminate or display an image.

Likely causes

1. Scalar Board Handshake Freeze: The internal processing board inside your HP monitor has locked up its HPD or HDCP state and needs a hard drain.
2. Cable Pin 20 Power Issues: Cheap, uncertified DP cables pass power along Pin 20 between the PC and monitor, causing protective power cutoffs on your graphics card.
3. Aggressive Power Saving (Auto-Sleep): HP's default energy saver modes sometimes deactivate the DisplayPort receiver bus completely when no active frame is rendered.
4. GPU Driver Negotiation Error: NVIDIA or AMD graphics drivers lose track of the monitor's EDID (Extended Display Identification Data) block after a sleep cycle or update.
5. Bent Port Pins: Physical wear or repeated cable swapping can push the delicate metal pins inside the female DisplayPort socket out of position.

Quick checks first

Before assuming your hardware is ruined, rule out simple configuration blocks:

• Reseat the connection: DisplayPort connectors feature small latching hooks. Make sure you fully press the release button on the cable plug and push it firmly into place until it clicks.
• Change GPU ports: Most desktop graphics cards offer 3 DisplayPort outputs. Swap to a different port to see if the issue is restricted to a single jack.
• Bypass docks and hubs: If you are using a USB-C dongle or KVM switch, connect the HP monitor directly to your PC or laptop to isolate the fault.

When it's a real hardware fault

If you have power-cycled the screen, swapped to a certified cable, and tested the monitor on a completely separate computer without success, the problem is likely localized to physical internal components.

Common hardware failures include:

• Damaged DP Socket: Inspect the socket on the back of the HP monitor with a flashlight. Look for a broken plastic alignment card or bent copper pins.
• Blown ESD Protection Diode: Electrostatic discharge from plugging in live DP cables can destroy the protection diodes directly behind the monitor port.
• Scalar Board Component Failure: A failed capacitor or degraded micro-controller on the main display board stops the monitor from processing video signals while keeping basic OSD features functional.

Soft resets vs board/panel work

Almost all initial DisplayPort signal errors can be resolved via software resets, input mode locks, and power drains. Soft resets pose no risk to your device and clear up 80% of DP handshake failures.

If the issue requires physical disassembly—such as desoldering a broken DP socket or replacing the HP main board—be aware that opening a monitor exposes you to high-voltage capacitors that remain charged long after power is pulled. For older displays, replacing the scalar board usually costs more than sourcing a modern replacement monitor.

Next steps

• Explore wider brand issues and common fixes across our HP hardware guides.
• Troubleshoot other monitor faults such as backlight bleed, flickering, or missing resolutions at the monitor problems hub.
• Thinking about upgrading instead of repairing? Check out our latest display analyses in the hardware review section.