January 14, 8:00AM EST. That is the official embargo for AMD’s Kaveri APU family, where it’ll presumably be finally launched to the public. Kaveri has been that shining light at the end of the tunnel for AMD and promises a massive boost to performance on the integrated GPU side as well as some parity, finally, with the performance of Intel’s processors. But because so many people are eager to find out more about this chip, slides given in confidence to attendees at the GPU 14 conference in Hawaii in September 2013 have managed to leak to the internet, courtesy of Pure PC. They include some interesting performance indications…
UPDATE: Pure PC has taken down the leaked article and apologised to their readers for the accidental slip of details.
“On this site was available live broadcast of the conference AMD Kaveri Tech Day 2014 in Las Vegas. The conference is covered by confidentiality (NDA), and unfortunately we can not reveal information on the latest AMD APU Kaveri, architecture and performance results of a new family APUs. Due to an error of our servers, the article was available for a short period of time. When an error is detected all the information along with photographs and slides were permanently removed from our servers. Sorry for misleading our readers. We have to suspend the publication of materials until the expiry of confidential (NDA). We will definitely return to you with a full report from the event AMD Kaveri Tech Day 2014 soon.”
Kaveri is the first APU that will be available to the public in socketed format for the desktop that has Steamroller CPU cores and Graphics Core Next (GCN) GPU cores in its physical make-up. Its very similar to the APUs already found in the Playstation 4 and Xbox One, but the CPU architectures are the main difference in addition to hardware unit counts (speaking in a broad sense, there are more differences between the two products). Theoretically, peak performance, measured at 856 GFLOPS, is closer to the A10-6800K than the APU inside the Xbox One (1.2TFLOPS) but actual performance in games on the desktop should be similar to what the One can push out.
Many of the details of Kaveri are still shrouded in secret for the moment, specially what changes may have been made to the memory controllers, where AMD beefed up the Steamroller design to make it batter than Piledriver, and what kind of power consumption and temperatures can be expected from a chip that has nearly a full Radeon HD7750 shoved into it. But performance is what Kaveri is all about, and the slides leaked today show a drastic increase in raw framerates compared to Intel’s Haswell processors.
In software benchmarks, Kaveri draws ahead over its rival, the Intel Core i5-4670K where it matters most – in graphics performance and in GPU compute scenarios. Performance in PCMark 8 is slightly higher than the A10-6800K as well, but the difference is much less higher than expected. This is mainly down to the memory controller and operating speeds – AMD is still using DDR3 with Kaveri and there will be a performance bottleneck imposed as a result, although the improvements that Steamroller and GCN are enough to push it to the top.
In 3DMark and Basemark CL, there is a massive lead generated by Kaveri and this can be attributed to how efficiently GCN chews through code. It scores almost twice as many marks in 3DMark than the Core i5-4670K, while generating a huge lead in OpenCL GPU compute scenarios thanks to GPGPU being one of the strengths that GCN has. Considering that it will probably also be cheaper than its Core i5 competitor, this is a win-win for consumers as well.
Synthetic benchmarks are one thing, though. Real-world gaming shows that, with a discrete graphics card, Kaveri’s Steamroller cores are working hard to allow it to draw up nicely with the gaming performance of the Core i5-4670K. Some games display a greater affinity for Intel’s cores while the majority appear to like Steamroller just as much. These are only average reported framerates, though, and it remains to be seen how Kaveri performs in frametime benchmarks for this assessment to hold any weight.
Pairing up both chips with the R9 270X is also a wise move, allowing AMD to mask any possible processor bottlenecks by using a mid-range GPU that just barely ticks all the boxes to play modern games with all the bells and whistles enabled. I expect that using anything stronger, like a R9 280X or higher, would reveal Kaveri’s limits pretty quickly. Note that this is also not using Dual Graphics, because pairing up Kaveri with anything more powerful than a Radeon HD7750 would result in the integrated graphics becoming a bottleneck for the system.
Gaming on Kaveri itself shows that the APU is running into memory bandwidth bottlenecks at 1080p. Bioshock Infinite at 1080p with low settings yields a respectable average of around 30fps, but this is typically what a Radeon HD7730 with DDR3 memory achieves on medium settings. Where a game doesn’t hit the memory bandwidth and is able to saturate all the GPU’s resources, though, it performs much better.
As these results are also not frametimes, they don’t have much weight to them. We need to see how Kaveri performs over time and in the most difficult scenarios, not an average that masks up all these issues. Until then, though, it’s nice to see that games from the Enemy Territory: Quake Wars era (2008-ish release) should run on High settings at 1080p without much trouble.