Question No video signal? [comprehensive troubleshooting completed]
Question No video signal? [comprehensive troubleshooting completed]
Hello,
I have assembled several PCs in my experience. This is the first time I've faced a problem that has proven difficult to resolve. Any help would be greatly appreciated!!!
Please read through all details before giving advice.
Hardware specifications:
- Motherboard: Asus TUF Z790
- CPU: i7-13700
- Power Supply: Asus TUF 750w
- RAM: Kingston Fury Beast DDR5 2x32GB
- SSD: Samsung 990 PRO 1TB
- GPU: ASUS ProArt GeForce RTX™ 4060 Ti 16GB OC Edition GDDR6
All components and cables are brand new, including the monitors. Purchases were made directly from ASUS or Amazon, and everything arrived in its original sealed packaging.
Issue: Regardless of my efforts, I am unable to obtain a video signal. When connecting an HDMI or DP cable, the monitor briefly displays "HDMI1" or "DP," but shortly after it shows "No video signal." Once the PC powers on, the motherboard's RGB lights illuminate, fans spin, yet no video appears. I've tested various keyboards, but pressing capslock or numlock does not trigger the indicator lights.
Troubleshooting steps:
1. Tested a different monitor (ASUS TUF Gaming 27" 1080P VG279Q3A) with another PC using both HDMI and DP cables. It worked flawlessly.
2. Used another monitor (LG UltraGear 27GN65S) as before; same results, it functions perfectly on a different PC.
3. Changed the monitor's HDMI/DP settings to match the new PC, but issues persisted.
4. Utilized the motherboard's HDMI and DP ports instead of the graphics card. Since the CPU includes an integrated GPU (non-F version), it should work but does not.
5. Removed the GPU and retested all steps; no improvement.
6. Verified RAM placement followed ASUS guidelines (slots A2 and B2, grey tabs), no change.
7. Swapped RAM sticks one at a time—no difference.
8. Disconnected the SSD and used a Windows 11 bootable USB drive; no change.
9. Jumped the CMOS, removed the battery from the motherboard, waited 10 minutes, then reinserted; no effect.
10. Switched to another new motherboard of the same type; no difference.
11. Replaced the CPU with a brand-new one; no change.
12. Updated the PSU and all cables; no improvement.
13. Restarted after each modification and thoroughly tested.
The only remaining options I'm considering are:
A. Order fresh RAM, possibly both sticks defective—planning to do so tomorrow.
B. Flash the BIOS; replacing the motherboard might resolve any BIOS-related issues.
C. It could be multiple parts failing, should I investigate further?
Is there anything else I should try?
Is your wall socket correctly grounded and properly wired?
What type of CPU cooler are you employing?
A motherboard won’t power on if it fails to recognize a functional cooler.
This could indicate a fan linked to the CPU fan port operating at 500rpm.
For clarity, remove all unnecessary parts from the case and connect only essential components:
Motherboard
cooler
minimum amount of RAM
Power Supply Unit (PSU) – ensure two 8-pin EPS connectors are present, as some boards require them.
Connect a monitor directly to the motherboard.
You should be able to view the BIOS screen.
A simple test is to run memtest, which boots from a USB drive.
The wall socket isn't used directly for powering the PC; it connects to my UPS (APC UPS 1500VA Battery Backup Surge Protector, BR1500G with AVR). My main PC is also connected through the same UPS and functions normally. I thought using the UPS would be better, but testing it directly on the wall didn't make any difference.
I have a Noctua DH-15 black CPU cooler. It seems to be one of the top choices available. It's installed correctly, both fans are working, and there are six screws involved. I don’t know how the CPU or motherboard would recognize its presence beyond the fan power supply.
Currently it’s inside the case with only a few components visible—those mentioned earlier. I could take it out, but that would be equivalent to removing the front panel power cables and case fans. There are four power cables connected: motherboard, GPU (unplugged), case fans, and front panel.
I’m having trouble accessing memtest; it won’t boot at all, which is the main problem. No BIOS screen appears.
I recently replaced my memory, but the only change was the RAM. After checking all other options and ruling them out, I’m left wondering—what’s the chance of getting two faulty Kingston RAM sticks?
If the NH-D15 fan connectors are linked to the CPU fan header rather than the CPU pump header, the cooler fan might seem to work at full speed, though it's actually not much on such a cooler. This could prevent the CPU from sensing any RPM on the CPU cooler fan port. The NH-D15 includes a fan splitter to power both fans together. It may be faulty or possibly not fully seated. Another aspect to inspect or confirm.
Understood, however, the fans would still function, though the BIOS or any program reporting fan information would display incorrect values. The last PC I assembled for me was air-cooled, but it incorrectly reported data for a water-cooled fan because the fan was connected to the wrong port on the motherboard. This issue wouldn't lead to the video problem.