AMD Introduces Precision Boost Overdrive 2, Boosts Single Thread Performance

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Pump up the voltage

If you've already bought, or plan on buying, a Ryzen 5000 processor, AMD just made the deal a whole lot sweeter. AMD's Precision Boost Overdrive (PBO) introduced one-click hassle-free overclocking to the masses for the Ryzen lineup of processors. Still, while the tech boosts performance in multi-threaded workloads, it has long failed to benefit single-threaded workloads. That changes in December when AMD's new Precision Boost Overdrive 2 (PBO2) lands in BIOS patches. The new PBO2 boosts single-threaded performance while retaining the benefits of the existing multi-core boosts, and even adds a little extra oomph there, too. 

The new PBO2 only works with Ryzen 5000 series processors, and AMD is also bringing in a new sophisticated undervolting technique to Ryzen 5000 processors for the undervolters among us.

We have plenty of testing that shows the benefits of PBO in our recent Ryzen 9 5950X and 5900X reviews, not to mention the Ryzen 5 5600X review. Still, AMD's impressive demo benchmarks show PBO2 basically enabling users to step up a tier over their existing processor in single-threaded performance. That's impressive given that AMD's Zen 3 processors have already soared to the top of the single-threaded performance benchmarks hierarchy.

For example, PBO2 grants the Ryzen 7 5800X nearly the same exceptional single-threaded performance of the beastly Ryzen 9 5900X. As with all overclocking, and AMD's policy with the first-gen PBO, the new PBO2 invalidates your warranty. But given the relatively risk-free performance gains we've seen with PBO, and the fact that the automatic nature of the feature avoids using excessively dangerous amounts of voltage, we think PBO2 overclocking will continue to be the safest path to wringing out the best performance possible. That said, proceed at your own peril. 

A few motherboards, like the MSI X570 Godlike and the Gigabyte X570 Aorus Master, already support the feature in current BIOS patches, but PBO2 officially lands in new BIOS revisions carrying the 1.1.8.0 AGESA, which will come to the masses in December. 

Silicon quality always varies from chip to chip, and based on how you did in the silicon lottery, your chip may have much higher overclocking potential than others. The PBO adaptive algorithm allows you to extract the utmost performance from your chip. As with first-gen PBO, the new PBO2 allows the processor to exceed the AM4 socket power limitations to boost performance based on your chips' capabilities, the power delivery given to the chip, and your cooling solution. 

The new Curve Optimization feature opportunistically adjusts voltage based upon operating conditions, such as if the processor is idling or under heavy load. This increases the range and impact of overclocking or undervolting, and is an automated feature. 

The feature now shifts from adjusting parameters via fixed voltages to applying new settings via "counts," which are worth approximately 3mV-5mW apiece. This gives the feature a dynamic range that allows for further automatic fine-grained tuning. Ryzen 5000 owners will have a range of 30 counts for adjustment. The adaptive algorithm adjusts these variables once every millisecond based on telemetry data fed over the Infinity Fabric from various on-chip sensors. 

Notably, the counts can be applied on either a per-core or entire-chip basis. 

PBO2 will debut as a BIOS-only option initially, but AMD plans to roll it into its Ryzen Master software early next year. For now, if you have a supported BIOS, you can activate the new automated overclocking feature by switching the BIOS settings to the 'motherboard' option, then enabling a higher PBO scalar limit and dialing in a 200 MHz max CPU boost override. From there, flip the switch on Curve Optimizer, and you're off to the races.      
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