"Per-clock efficiency" is generally not goal in itself in CPU design, absolute performance and efficiency are. Where AMD has stumbled is getting the clock up, probably partly related to their unfortunate fab situation
The speed-demon strategy has seen successes historically, Pentium 4's fate notwithstanding. See eg the DEC 21164 and the IBM z196.
There was a lot more wrong with the P4 (not the least of which was the absolutely abysmal chipset Intel married it to) that rendered it such a disaster.
Bulldozer was always supposed to be a high clock long pipe machine, sacrificing some IPC. See eg http://www.anandtech.com/show/5057/the-bulldozer-aftermath-d...
"Per-clock efficiency" is generally not goal in itself in CPU design, absolute performance and efficiency are. Where AMD has stumbled is getting the clock up, probably partly related to their unfortunate fab situation
The speed-demon strategy has seen successes historically, Pentium 4's fate notwithstanding. See eg the DEC 21164 and the IBM z196.