PC turns on but no display

Use this when a PC turns on but there is no display: fans or lights respond, but the monitor stays blank. The same steps cover a CPU that is on but has no display, and a PC that is not displaying on the monitor. For notebooks start at laptop no display but power on and run the external monitor test first.

Is this the right page?

Stay here if a desktop or tower has power signs (fans, LEDs) but the monitor stays black or says no signal.
No fans and no LEDs → power-supply / wall power triage (not this page).
Laptop panel dark → use the laptop diagnosis page, not this desktop guide.

Desktop steps

Step 1. Confirm PSU fans and monitor input

Listen for case or GPU fans. Turn the monitor on and pick the same HDMI / DisplayPort / VGA input as your cable. Try a second known-good cable. If the monitor has a built-in self-test with only the power cable attached, use it to prove the panel itself works.

Desktop case with spinning fans and monitor input selected on the OSD — Power without video still needs a proven display path.

Step 2. Try motherboard video vs GPU port

If the CPU has integrated graphics, move the cable to the motherboard I/O ports. If you only have a discrete GPU, seat the cable firmly in that card’s ports — not an empty motherboard HDMI that has no GPU behind it. Wrong port is a common “PC on, no display” miss.

Rear I/O: discrete GPU ports marked correct, motherboard HDMI marked wrong when a discrete GPU is installed — Remove ambiguity about which engine is driving the cable.

Step 3. Reseat GPU and RAM

Unplug AC, hold the case power button about 10 seconds, reseat the graphics card (including any 6/8-pin PCIe power) and DIMMs, then retry. Loose GPU power or a half-seated card often looks exactly like “fans spin, no video.”

Hands reseating a graphics card and DIMM modules with power unplugged — Unplug AC and hold the case power button before touching cards.

Step 4. Minimal boot configuration

One RAM stick in the primary slot, onboard video or a single GPU, no extra USB devices. Still dark? Read motherboard debug LEDs or beep codes in the OEM manual (Dell and others publish no-POST / no-video trees).

PC motherboard with only one RAM stick and necessary power cables — Strip accessories until you get POST.

Step 5. Safe Mode and display drivers (only after you have any video)

If you can reach Safe Mode or an intermittent desktop, open Device Manager → Display adapters and update or roll back the GPU driver. Do not edit TdrDelay. Prefer Windows Update or NVIDIA / AMD / Intel official pages — not third-party packs. Do not edit TdrDelay. For the recovered-driver dialog, see display driver stopped responding.

Desktop with spinning fans and monitor input selected — same power-path check before driver work — Driver work needs a visible desktop or Safe Mode first.

FAQ

CPU is on but no display — same guide?

Yes. If the CPU is on but there is no display, or the PC is not displaying on the monitor, stay on this page. Fans and board lights without a picture use the same checks: monitor input, cable, GPU port, then RAM.

Monitor shows No Signal — is the PC dead?

Not yet. Confirm the monitor works on another machine, swap cables, change the OSD input, and try another video port. See also the HDMI no-signal guide.

How does this relate to the laptop guide?

Same idea: prove the display path first, then memory and GPU. Laptops return to the home diagnosis tree for panel and backlight steps after an external monitor works.

Should I download a DLL or one-click GPU fixer?

No. Use Windows Update or NVIDIA, AMD, or Intel’s official driver pages — or your OEM’s support download for that model. Do not edit TdrDelay.