PC randomly powers off only during GPU-heavy workloads
Environment
Core i7 system with an RTX 4080 Super and a five-year-old 750 W PSU.
What happens
The machine loses power instantly during rendering or gaming, with no blue screen.
What I have tried
Monitored CPU and GPU temperatures; both remain below 75°C.
I would appreciate advice on how to identify the root cause without risking existing data or configuration.
Verified community troubleshooting
A safe way to narrow this down is to change one variable at a time.
Likely cause: Transient GPU power spikes trigger over-current protection in the aging power supply.
What I would try: Test with a known-good ATX 3.x power supply of suitable capacity and use separate PCIe power leads instead of daisy chaining.
If this is a production system, test the change during a maintenance window.
The rollback advice is helpful. I will take a snapshot or export the configuration before testing.