Why does my GPU need more power than its TDP?
TDP (Thermal Design Power) is the average power draw, not the maximum. Modern GPUs can spike 30-50% above TDP during sudden load changes—these transient spikes last milliseconds but can trip PSU protection circuits if there's not enough headroom.
What PSU wattage do I need for an RTX 4090?
NVIDIA recommends 850W, but for comfortable headroom with transient spikes (up to 600W), a 1000W PSU is ideal. With a high-end CPU, consider 1200W. Quality matters more than raw wattage—a good 850W PSU often outperforms a cheap 1000W unit.
Can a PSU be too powerful for my system?
No, a larger PSU won't harm your system—components only draw what they need. However, PSUs are most efficient at 50-60% load. A 1000W PSU running a 200W system operates at low efficiency. There's also the cost factor: you're paying for unused capacity.
What causes random shutdowns during gaming?
Often it's the PSU hitting its over-current protection (OCP) during GPU power spikes. Even if your PSU handles steady-state load, transient spikes can trigger protection circuits. Solutions: upgrade PSU, ensure good ventilation, or slightly undervolt the GPU.
Does PSU efficiency rating (80+ Bronze/Gold/Platinum) matter?
Efficiency affects electricity waste as heat, not power delivery. An 80+ Gold 750W PSU delivers the same 750W as an 80+ Bronze—it just wastes less power doing so. Higher efficiency also usually indicates better build quality and components.
What is the 12VHPWR connector?
The 12VHPWR (12+4 pin) connector is a new standard for high-power GPUs like the RTX 4090. It can deliver up to 600W through a single cable. Early versions had melting issues—ensure the connector is fully seated and not bent at sharp angles.