Thats not a very good way of guessing performance increase, turbo is not an off or on switch. It ignores any delta in head room between bulldozer based SOC's and piledriver based SOC's. If you look at Trinity based SOC's and the fact they can get a 3.4/4.0 quadcore with a 384:24:8 ALU/mtu/rops @ 700mhz in a 65watt TDP when the GPU alone would pull somewhere around 35-40 watts ( the most efficient Turks pro pulls 45watts) it is obvious that there is significant headroom when operating within the 3ghz power range.
Bulldozer struggles to get off base clock in high throughput Floating point workloads and this can be seen with its very high turbo's. That's a big reason why your 5.4% clock increase isn't a very meaningful number. Trinity on the other hand has comparable clocks, lower base to turbo delta's, lower TDP and a GPU. To put it simply you can't make assumptions about how piledriver will clock based of bulldozers experience. One of the big reason for this is because the high power draw areas have been transitioned from soft flip flops to hard flip flops.
From there you also have to consider Integer and Floating point workloads separately. Integer workloads are up 10%-15% per clock vs bulldozer. Floating point on the other hand is less as part of the FPU wasn't broken like it was with bulldozer, it still benefits from bigger TLB's more flexibility in the LSU etc depending on workloads 0%-7% per clock has been seen for Trinity has been seen.
So i think your clock increase is to pessimistic and the "IPC" increase is way to variable to have a single value.
its now 1:30am and this dyslexic mans going to bed ( sorry if this post is unreadable, i tried but im tired......lol)
edit:
thats one of the big main things. going hard flip flops is another. These are physical changes, if your just taking about an architecture and not how it is implemented then that kind of stuff is abstracted away.I thought the biggest change was the new resonant clock mesh design?
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