It seems unlikely AMD could in its dire financial straits come up with any miracles, so it's safe to assume the CPU will be in the same neighbourhood as the other CPUs in the market currently, not around 10GHz unless it eats half a kilowatt of power. The same also means it has to have decent clocks to compete with anything. If it has very low clocks, it might indicate it's not very stable. I have said it before in GPU threads, but clocks are free performance as long as the processor can take it (look at Pascal). Increasing IPC wonderfully means more complexity or some ingenious novel design that AMD probably couldn't afford to develop. So, it's useless to expect Zen to beat Intel's offerings with much lower clocks. However, if it has a bit higher clocks than the rumours indicated, it might mean it clocks very nicely architecturally, which would be jolly good indeed.