Thermaltake AC0015 Dr. Power II Power Tester Features: Designed from the ground-up to support every ATX power supply available today up to ATX12V v2.3. Oversized LCD panel that accurately shows the value of each specific power rails (within one-tenth of a volt). Accurate voltage indicating for +12V/+5V/+3.3V/5VSB/ -12V. Built-in output connectors diagnostic system, low-voltage, high-voltage, no voltage, PG alarm systems. Easily troubleshoots system failure due to unstable power supply. Built-in alarm system to identify user when the power supply demonstrates abnormal characteristic.