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Quick answer: On AMD Ryzen, enter the BIOS and set Curve Optimizer to Negative 10 on all cores, then stress test and step toward Negative 20 if stable. On Intel, use the BIOS CPU Core Voltage Offset starting at -0.05V (or Intel XTU in Windows where supported). After every change run a 10 minute stress test and watch temperatures drop at unchanged performance.
Step 1 – Record your baseline
Install HWMonitor or HWiNFO, run a 10 minute Cinebench or similar loop, and note peak temperature, clock speed and score. These three numbers are how you will prove the undervolt worked and did not cost performance.
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Pairing your undervolt with a stronger air cooler drops temps further for very little money.
Step 2 – AMD: Curve Optimizer
Reboot into the BIOS (Del during boot) and find Curve Optimizer under AMD Overclocking or Precision Boost settings. Set All Cores, Negative, magnitude 10. Save, boot, stress test. Stable? Go to 15, then 20. Most chips live happily between Negative 15 and 30; laptops often expose the same via the maker’s tuning app instead.
Step 3 – Intel: voltage offset
In the BIOS voltage section, find CPU Core Voltage Offset, set mode to Offset with a negative sign, and start at 0.050V. Test, then step by 0.010 to 0.025V. Many 12th generation and newer boards also allow Lite Load / AC loadline reductions that achieve the same result. Note that some newer locked laptops disable undervolting entirely; if the option is missing, that is why.
Step 4 – Prove stability like you mean it
After each step: 10 minutes of stress load, then a normal reboot cycle. When you reach an offset that crashes, freezes or throws WHEA warnings in Event Viewer, retreat one step and run a longer test: an hour of mixed load, a gaming session, and one full cold boot the next day. Idle instability appears at aggressive offsets even when load is stable, so give it a normal week before declaring victory.
Pair it with real cooling
Undervolting plus a competent cooler is how quiet PCs are built. If temperatures are still high after tuning, revisit the mounting with our thermal paste guide or step up the hardware: best CPU coolers, best air coolers and low profile options for small cases.
Frequently asked questions
Is undervolting safe for my CPU?
Yes: you are feeding the chip less voltage, not more, so there is nothing to burn. The only risk is instability, a crash or freeze when the offset is too aggressive, which you fix by stepping the offset back. Settings reset with a BIOS clear, and no permanent change is made to the silicon.
How much lower will my temperatures go?
Typical results are 8 to 15 degrees under full load, and often more on laptops and compact builds where cooling is tight. Because boost algorithms are thermally limited, many chips actually score slightly higher after undervolting: cooler silicon holds boost clocks longer.
Undervolting versus underclocking: what is the difference?
Undervolting keeps the same clock speeds at lower voltage, so performance stays equal or improves. Underclocking reduces the speed itself and costs performance. You want undervolting: the free temperature drop with nothing traded away when tuned correctly.
Small offsets, one stress test per step, and you bank a double-digit temperature drop at identical performance. It is the best free tune a modern CPU can get.
