AMD Succeeds in its 25x20 Goal: Renoir Crosses the Line in 2020

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One of the stories bubbling away in the background of the industry is the AMD self-imposed ‘25x20’ goal. Starting with performance in 2014, AMD committed to itself, to customers, and to investors that it would achieve an overall 25x improvement in ‘Performance Efficiency’ by 2020, which is a function of raw performance and power consumption. At the time AMD was defining its Kaveri mobile product as the baseline for the challenge – admittedly a very low bar – however each year AMD has updated us on its progress. With this year being 2020, the question on my lips ever since the launch of Zen2 for mobile was if AMD had achieved its goal, and if so, by how much? The answer is yes, and by a lot.

In this article we will recap the 25x20 project, how the metrics are calculated, and what this means for AMD in the long term.

Renoir 2020: New Silicon, Goal Achieved

The announcement today from AMD confirms the company has reached its goal of 25x performance efficiency by the end of 2020, starting from the Kaveri baseline. Here’s the important graph:
 

As we can see using this metric, there were big jumps from Kaveri to Carrizo, Bristol Ridge to Raven Ridge, then a series of stagnation over Zen/Zen+, before finally a bump up to Renoir. This gives three distinct jumps:

• Kaveri to Carrizo was 3.5x,
  
• Bristol to Raven was 2.2x,
  
• then Picasso to Renoir was 2.92x
  

The base value for AMD’s goal is on its Kaveri mobile processors, which by the standards of today set a very low bar. As AMD moved to Carrizo, it implemented new power monitoring features on chip that allowed the system to offer a better distribution of power and ran closer to the true voltage needed, not wasting power. After Carrizo came Bristol Ridge, still based on the older cores, but used a new DDR4 controller as well as lower powered processors that were better optimized for efficiency.

A big leap came with Raven Ridge, with AMD combining its new highly efficient Zen x86 cores and Vega integrated graphics. This heralded a vast improvement in performance due to doubling the cores and improving the graphics, all within a similar power window as Bristol Ridge. This boosted up the important 25x20 metric and keeping it well above the ‘linear’ gain.

From 2017-2019, this was ultimately a lull in AMD’s strategy, namely because there were no significant design changes. The versions of 2017/2018 Raven Ridge come down to slight SKU differences used for the metric, but ultimately when it came time to measure the systems AMD was a little out of cycle here. Moving from Raven Ridge to Picasso was a shift from using GlobalFoundries 14nm to 12nm, which affords a slight power gain but not so much on the performance.

Going from 2017 to 2019 still yielded a 23.5% gain within the same product family, mainly due to minor manufacturing updates and better binning or power algorithms. It was around the Picasso time when OEM’s started taking AMD’s notebook platform more seriously, especially as the lead up to 2020’s Renoir.

The jump from Picasso to Renoir has been well documented. Our first use of the CPUs, reviewed in the ASUS Zephyrus G14, left us with our mouths open, almost literally. We called it a ‘Mobile Revival’, showcasing  AMD’s transition over from Zen+ to Zen2, from GF 12nm to TSMC 7nm, along with a lot of strong design and optimization on the graphics side. The changes from the 2019 to the 2020 chip include doubling the core count, from four to eight, improving the clock-for-clock performance by 15-20%, but also improving the graphics performance and frequencies despite moving down from an silicon design that had 11 compute units down to 8. This comes in line with a number of power updates, adhering to AHCI specifications, and as we discussed with Sam Naffziger, AMD Fellow, supporting the new S0ix low power states has helped tremendously. The reduction in the fabric power, along with additional memory bandwidth, offered large gains.
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