GPU PSU & Thermal Sanity Check

GPU PSU & Thermal Sanity Check

Power supply sizing · connector safety · thermal headroom estimator

Start by selecting your GPU and CPU from the first two dropdowns — each entry shows the component's TDP in watts so you can immediately gauge power demand — then pick your case type from the airflow profile list, ranging from Mini-ITX (poor) to Full Tower (excellent). Hit Calculate ⚡ and the tool instantly runs four checks in parallel. The Power Breakdown section shows animated bars for every system component — GPU, CPU, motherboard platform, and miscellaneous draw — totaling your real system wattage and flagging the minimum PSU size with a mandatory 20% headroom buffer. The PSU Sizing Guide then highlights exactly which wattage tier is your minimum and which is the recommended sweet spot for overclocking headroom. The Connector Safety panel lists up to four connector options for your specific GPU — rated Recommended, Acceptable, Risky, or Insufficient — with plain-English notes explaining why; RTX 4090 and 5090 owners will see an explicit warning against 3×8-pin adapters due to documented melting risk. Finally, the Thermal Headroom arc gauge scores your case airflow from 1 to 4 and estimates your GPU junction temperature adjusted for that airflow penalty, so you know before you build whether your case will keep temperatures in a safe range or push you toward undervolting and extra fans.