AMD Zen 2 May Feature Major IPC Uplift and CCX Rework
Since the launch of Ryzen, AMD has been shaking things up in the CPU market. Due to the new Zen architecture, the Red team is now competitive with Intel. This year, the company followed up with the new Zen+ chips, with minor tweaks. For next year, things are heating up again according to the roadmap. According to some new rumours, Zen 2 will be bringing some impressive IPC improvements and massive rework to CCX. The IPC will reportedly increase by 10~15% and CCX core counts up to 8.
It’s important to state that these rumours are just that right now. However, they do jive with what we already know from AMD. This gives us an opportunity to see what Zen 2 will offer. First up is the IPC gain. AMD has been targetting a major 10-15% IPC lift for each new major Zen refresh. Based on what we saw with Zen, the numbers are likely to be in the high end. AMD also left room in Zen for improvement and 15% seems to be a modest claim. This would bring Zen to essentially Skylake/Kaby Lake IPC.
Another choke point in Zen is the CCX. Due to the design, multi-thread efficiency is somewhat low once you move out of the basic 4 core CCX. Infinity Fabric while great, certainly has room for improvement. AMD has already hinted at increased CCX core counts. An increase to 6 cores is already expected with Zen 2 but a move to 8 makes just as much sense. With the improvements in 7nm, there is a lot of extra die space for AMD to work with. Fitting 8 cores allow for mainstream 16 core CPUs as well as better multi-threaded efficiency. This is important for the enterprise market.
Finally, with 7nm, AMD gains basically free performance (frequency) and efficiency (power consumption) improvements. So far, it looks like everything is on schedule for a release in the first half of 2019. Select customers could even receive chips later this year. Once they do, we can expect more leaks that could confirm the IPC or CCX core counts. With these new processors, it will be interesting to see how the market changes as Intel faces increased competition.
I don’t personally think we will see a general IPC increase of 10 – 15% I believe we will see 15% in applications where AMD struggles today maybe even 20% in some outliers, but I believe on average you will be more looking at 5% -7% on average. The big “IPC” increases will be from reductions in infinity fabric latency.
I am 99% sure about a 12 core die however, whether all the cores are enabled at launch for the first mainstream parts that is another question, if it does go to 16 cores which I am far less certain of, because it’s just not required to compete with Intel. They could do 48 cores and Intel wont be able to touch that until they get EMIB good enough to be a interconnect for multiple dies.
If AMD is even just competitive with Intel on IPC have 48 cores and AMD will definitely have better clockspeeds than Intel’s 14nm because they are going to be using TSMC’s 7nm, which TSMC’s 16nm has about a ~10% performance advantage over Global Foundries “12nm”
a 25% clock speed increase is well within reason for TSMC 7nm over Global Foundries 12nm, which a 25% increase to a 2700X max boost clock would be 5.375Ghz. And a 25% improvement is conservative, that is only for the max boost though you all core clock speeds I would put the improvment at something like 5% to 10% at 10% though you are talking 4.3Ghz on a 12 core CPU thats pretty freakin good.
its not 8 cores per ccx. its 4 cores per ccx. 2 ccx’s per die. same as first gen ryzen. a lot of people seem to think that first and second gen ryzen were 2 chips but it was a single die. a single chip. not 2. and these new zen 2 dies will be the same