AMD Succeeds in its 25x20 Goal: 2020 "Renoir" Over 31 Times More Efficient than 2014 "Kaveri" Chips
takyon writes:
AMD claims to have improved performance by about 5x while cutting power use to about 1/6th, when comparing 2014 "Kaveri" mobile APUs to 2020 "Renoir" mobile APUs. This exceeds a goal of improving efficiency by 25x by 2020:
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.
[...] 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.
AMD accomplished this while using refined "7nm" Vega GPU cores in its APUs, instead of moving to a newer architecture such as RDNA2.
Read more of this story at SoylentNews.