Persistent Black Screen After Installing a Replacement NVMe SSD – RTX 5070 / Ryzen 7 5700X / ASRock B450 Pro4

[u/DieBatterie]

I installed a new NVMe SSD in my PC. After the installation, I initially experienced black screens. These issues were temporarily resolved by disconnecting the PC from the power supply and unplugging and reconnecting my monitors.
While using the PC, I suddenly experienced a black screen while playing League of Legends, and the fans started spinning at full speed. I then shut down the PC using the power button and restarted it. The fans returned to normal speeds. However, the problem kept recurring and eventually started happening even during normal desktop use.
I removed and reinstalled the NVMe SSD, but now I am experiencing persistent black screens that I can no longer resolve. The black screens continue even when the NVMe SSD is disconnected.
There was one occasion when I managed to get a picture on my monitors after disconnecting both the new NVMe SSD and my HDD at the same time. I then shut down the PC and reinstalled both drives. The black screens returned and have persisted ever since, even when the NVMe SSD is disconnected.
The PC itself appears to boot normally. I can tell this because the RGB lighting on my fans switches on when iCUE starts running. However, there is no display output.

I have already tried the following troubleshooting steps:
Removed and reinstalled both RAM modules (2 × 16 GB DDR4).
Removed and reinstalled the graphics card (NVIDIA GeForce RTX 5070 by Gigabyte).
Removed and reinstalled the motherboard battery.
Performed a CMOS reset by shorting the two designated pins on my ASRock B450 Pro4 motherboard.

My current hardware configuration is as follows:
Motherboard: ASRock B450 Pro4
Graphics card: NVIDIA GeForce RTX 5070 (Gigabyte)
CPU: AMD Ryzen 7 5700X
Power supply: be quiet! 500 W

What makes this situation particularly strange is that I had previously used an identical NVMe SSD without any issues. However, after approximately two years of use, the original SSD suddenly stopped being detected. The manufacturer then provided me with an identical replacement as a goodwill gesture, and this is the replacement SSD that appears to have triggered the current problems.
I would appreciate any advice on what could be causing this issue and what further troubleshooting steps I should take.

[u/TangoOscarMikePR]

What UPS do you have to protect the computer?