Where are you drawing that conclusion from? None of those graphs have data for any of the K6 series.
My mistake. I read "3DNow!" and my brain inserted "K6 with 3DNow"
- edit - I've finally found a benchmark that includes an early Athlon and a K6-2:
http://www.tomshardware.com/reviews/mother-cpu-charts-part-2,944-19.html
Pretty big difference there! The K6-2s are mostly missing from the benchmark results preceding and following that one. A quick calculation (which may be incorrect) suggests that clock-for-clock the Athlon was twice as fast as the later K6-2s, but a broader range of benchmarks would help clarify the result. My calculation for the WinRAR results draw a different picture though (my calculation was time in minutes * K6 clock speed / athlon clock speed), they're almost the same in that respect.
I'm surprised you didn't think of the IPC jump Conroe had over Prescott.
I thought of it later:
http://forums.anandtech.com/showpost.php?p=35625432&postcount=36
Perhaps the jump to SB from Conroe stands out in my mind more because a) it was more recent and b) it was basically a coup de grace against AMD and dispelled any notion that AMD was going to catch up at any point soon, because it showed Core i3 SBs spanking the best of AMD's line in a lot of cases.
Because it's super late. As always.
Probably fab problems again.
As much as I liked AMD (and in the days of AMD CPUs in nForce boards, I loved them! Cheap, decent performers with reasonable chipset QA!), and I appreciate the benefits of competition, Intel would need to screw up big time (ie. miss an enormous opportunity) for AMD to regain the lead on desktop CPU performance (probably mobile too, I don't pay much attention to it). The IGP gaming market is a bit of a bizarre one to aim for IMO. Perhaps that and the ATI markets are the best that AMD can hope for right now?