Despite AMD’s currently abysmal laptop marketshare, the company claims a lot of historical firsts over the past 10 years. AMD’s U-series are lower power profile, integrated graphics parts. H-series are discrete CPU with higher TDP. Pro series isn’t available yet, but targets enterprise with additional security features. AMD AMD’s been on top with integrated graphics…
AMD has scored big 7nm performance wins over the last few months with its Ryzen 3000-series desktop CPUs, Threadripper 3000-series HEDT CPUs, and Epyc Rome server CPUs—and the newest addition to the family, the Ryzen Mobile 4000 series, looks like it will continue in the same vein.
No one should be surprised that the Ryzen Mobile 4000—which brings AMD’s Zen 2 7nm architecture to the laptop world—outperforms Intel’s laptop CPU offerings on multi-threaded performance or graphics performance. Even single-threaded performance—which has finally achieved par—isn’t the big stumbling block we’ve been waiting to see if AMD could conquer.
The egregious black mark against AMD’s mobile line over the last year or two hasn’t been about performance at all—at first glance, it’s about battery life. At a second, closer look, it’s even more about OEM integration. We’re pleased to see that AMD has taken giant strides to improve both issues with this year’s mobile CPU lineup.
Getting serious attention from OEMs
Although last year’s Ryzen Mobile 3000 line didn’t use AMD’s newest Zen 2 architecture or 7nm process size, it was still a solid match for its Intel competition on paper. Unfortunately, a good mobile CPU isn’t enough to make a good laptop. Despite performance that ranged from “solid competition” to “outright winner” compared to Intel designs, most Ryzen 3000 laptops had poor battery life, poor thermal design, and mediocre performance at best.
The problem is that laptop OEMs weren’t taking the Ryzen Mobile 3000 seriously. They generally lavished attention to detail on Intel-powered designs for higher-end laptops while shoveling Ryzen CPUs into generic designs aimed at cost-is-the-only-object buyers.
Hardware integration isn’t a really crucial factor with desktops or even servers. They can afford to devote extra space, weight, and power to offset minor inefficiencies—but in a laptop, any sacrifice in design and integration quality translates to obvious, user-visible penalties.
The most common complaint with Ryzen 3000 laptops is poor battery life. But performance takes a hit from sub-par integration work as well. Modern laptop designs generally spec a TDP (Thermal Design Power) budget for cooling that’s insufficient to handle the total heat the system’s components can produce when running flat-out for long periods.
Since the system can’t handle full system load for long periods, it throttles performance on the components as necessary to avoiding cooking them in their own waste heat. This is why poor laptop design results in poor performance—a less-efficient system generates more heat, exceeds the TDP budget more quickly, and the system must slow itself down as a result.
This year, it seems clear that AMD has gotten OEMs’ attention and has them on board with producing detailed and fully integrated Ryzen 4000 system designs. AMD had a Lenovo executive take the stage to talk about the upcoming Yoga Slim 7, an ultrathin 14″ laptop with high performance and long battery life—but Lenovo is unlikely to be the only OEM paying attention.
Although AMD is being cagey for the moment about exactly who is or isn’t on board, the company specifically talked about partnerships with Microsoft and Google as well as new design certification and continuous validation programs aimed at fixing any problems with poor integration going forward.
We went into AMD’s Tech Day—the press-invite-only launch for the Ryzen Mobile 4000 line—excited about the potential performance to be found in the new 7nm design. But we had real concerns about battery life. To overcome user dissatisfaction with earlier AMD powered laptops, the company needed both to improve OEM and OS vendor-integration efforts and improve the direct hardware efficiency in its own designs significantly.
Happily, AMD seems to have done exactly that. Both the general presentations and a specific breakout on power and thermal efficiency made very clear that AMD took this aspect of the Ryzen Mobile 4000 very seriously. The company claims overall System-on-Chip power reduction of 20 percent and a multi-threaded, heavy-load performance-per-watt twice that of earlier designs.
Shrinking die size from 12nm to 7nm alone might account for as much as half of the increase in efficiency, but the rest comes from significant design improvements. In particular, the Renoir design incorporates the newest ACPI power-state model—which includes three separate low-power c-states to shut down portions of the CPU, instead of the earlier design’s one.
Renoir also adds new OS hinting features. Operating systems supporting the new ACPI model—including both Windows and Linux—can inform the CPU what performance levels are expected for upcoming workloads, and how best to choose between higher frequencies and lower power draw.
Finally, entry and exit latency from the lower-power C-states is drastically improved, allowing the CPU to spend more time in lower-power idle modes, with less impact on user-perceived task latency.
Listing image by AMD