> ## Documentation Index
> Fetch the complete documentation index at: https://docs.derekdinh.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting a PC That Produces No Display Signal

> Diagnose and fix a PC that powers on but shows no video: check cables, input sources, RAM, GPU seating, integrated graphics, and BIOS beep codes.

A blank screen after powering on your computer is one of the most alarming hardware problems you can encounter, but the root cause is often something straightforward. Work through the steps below in order — most no-display issues are resolved before you reach the advanced checks.

<Steps>
  <Step title="Check Physical Cable Connections">
    A loose or damaged video cable is the single most common cause of a blank display. Before assuming hardware failure, verify every connection.

    * Unplug and firmly re-seat the video cable (HDMI, DisplayPort, or VGA) at **both** ends — the monitor and the graphics card/motherboard port.
    * Inspect the cable for bent pins (VGA), broken locking tabs (DisplayPort), or visible kinks.
    * Ensure you are plugging into the **dedicated GPU** output ports (usually on the lower half of the rear I/O panel) rather than the motherboard's integrated ports — unless you are intentionally testing integrated graphics.

    <Note>
      If your GPU has multiple output ports (e.g., three DisplayPort and one HDMI), try each port in turn. Some cards disable unused outputs depending on driver state and active-port detection.
    </Note>
  </Step>

  <Step title="Verify the Monitor's Input Source">
    Monitors with multiple inputs will display a blank screen if they are listening on the wrong source, even when the PC is sending a valid signal.

    1. Press the monitor's physical **Menu** or **Input** button.
    2. Cycle through available sources (HDMI 1, HDMI 2, DisplayPort, VGA, USB-C) until you reach the one your cable is connected to.
    3. Confirm the monitor itself powers on and its status LED is white or blue (not amber/orange, which indicates standby).

    <Tip>
      If the monitor shows an on-screen menu when you press its buttons, the panel itself is working correctly — your investigation should focus entirely on the PC and the cable.
    </Tip>
  </Step>

  <Step title="Test With a Different Cable and Monitor">
    Isolate whether the problem lives in the cable or the monitor before digging deeper into the PC.

    * Swap in a known-good cable of the same type. Even brand-new cables can be defective.
    * Connect the PC to a different monitor or TV. HDMI-equipped televisions work well as a quick substitute display.
    * If the substitute display works, the original monitor is faulty or set to the wrong input. If the substitute also shows nothing, the problem is on the PC side.
  </Step>

  <Step title="Listen for POST Beep Codes">
    When the system powers on, the BIOS runs a Power-On Self-Test (POST). If it detects a failure, it emits a series of beeps through the motherboard speaker before video initialises.

    | Beep Pattern (IBM-style BIOS) | Likely Cause                   |
    | ----------------------------- | ------------------------------ |
    | 1 short beep                  | POST passed — look elsewhere   |
    | 1 long + 2 short              | GPU / video card failure       |
    | 3 long                        | Keyboard / keyboard card error |
    | Continuous long beeps         | RAM not seated or incompatible |
    | No beeps + no display         | No speaker, or CPU/PSU issue   |

    <Note>
      Beep code meanings differ between BIOS vendors (IBM, AMI, Award, Phoenix). The table above reflects the common IBM-style codes. AMI BIOS, for example, uses sequences of short beeps (e.g., 8 short = video memory failure). Consult your motherboard manual or manufacturer website for the exact codes used by your board.
    </Note>
  </Step>

  <Step title="Reseat RAM Modules">
    Improperly seated RAM is a leading cause of no-POST and therefore no video output.

    1. Power off the PC and unplug the power cable.
    2. Open the side panel and locate the RAM sticks (long rectangular modules in slots near the CPU).
    3. Press down the retention clips on both ends of each slot until the stick pops upward.
    4. Remove each stick, then firmly re-insert it until **both** clips click back into place.
    5. If you have multiple sticks, try booting with **only one stick** installed in the primary slot (usually labelled A2 or DIMM1 — check your manual).

    <Warning>
      Always discharge static electricity by touching an unpainted metal surface or wearing an anti-static wrist strap before handling memory modules. Static discharge can permanently damage RAM and motherboard slots.
    </Warning>
  </Step>

  <Step title="Reseat the GPU">
    A GPU that has shifted in its PCIe slot will fail to initialise, producing no display output even if the system otherwise appears to power on.

    <Warning>
      Power off and unplug the PC before handling the GPU. Discharge static electricity by touching an unpainted metal surface or wearing an anti-static wrist strap — GPUs are sensitive to electrostatic discharge.
    </Warning>

    1. With the PC powered off and unplugged, remove the GPU's PCIe power connectors (6-pin or 8-pin cables from the PSU).
    2. Release the PCIe retention latch at the end of the slot and slide the card out.
    3. Inspect the gold edge connector for dust or oxidation — gently clean with a dry, lint-free cloth if needed.
    4. Re-insert the card firmly until the retention latch clicks, then reconnect the power connectors.
    5. Ensure the GPU's bracket screws are tightened into the case.
  </Step>

  <Step title="Test With Integrated Graphics">
    If your CPU has an integrated GPU (most Intel Core processors and AMD Ryzen APUs do), you can use it to determine whether the dedicated GPU is faulty.

    1. Remove the dedicated GPU from the PCIe slot.
    2. Connect your monitor cable directly to the **motherboard's** video output port (on the rear I/O panel, near the USB and audio ports).
    3. Power on. If you now see video, the dedicated GPU is likely defective.
    4. You may need to enter BIOS and enable the integrated graphics option (often labelled **iGPU**, **Integrated Video**, or **Primary Display → CPU Graphics**).

    <Note>
      Not all CPUs include integrated graphics. AMD Ryzen X-series CPUs (e.g., Ryzen 5 5600X) have no iGPU. Check your CPU specifications before proceeding.
    </Note>
  </Step>

  <Step title="Clear the CMOS">
    A corrupted BIOS configuration can sometimes prevent POST from completing. Resetting CMOS clears all BIOS settings back to factory defaults.

    1. Power off and unplug the PC.
    2. Locate the round, silver CMOS battery on the motherboard (similar in size to a watch battery).
    3. Remove the battery and wait **60 seconds**.
    4. Re-insert the battery and power the PC back on.

    Alternatively, most motherboards have a dedicated **CLR\_CMOS** jumper or a rear-panel CMOS reset button — consult your manual for its exact location.
  </Step>

  <Step title="Escalate to Tier 2 Support">
    If none of the above steps restore video output, the issue likely requires component-level diagnosis or replacement.

    <Accordion title="Information to gather before escalating">
      * Make, model, and age of the PC and monitor
      * GPU model (check the sticker on the card or the purchase receipt)
      * Which steps you completed and the result of each
      * Whether any beep codes were heard, and the exact pattern
      * Any recent hardware changes (new RAM, PSU swap, case move)
      * Whether the PC was ever working with this monitor and cable combination
    </Accordion>

    Possible outcomes at Tier 2 include GPU RMA, RAM replacement, or motherboard diagnosis. Do not continue swapping components without a structured test plan, as this can introduce additional faults.
  </Step>
</Steps>