None of K8 architecture doesn't support HT (as Hyper Threading), and K8L or so called K10(.5) already get improved controller but AMD didnt resolve issues like broken half multi compatibility since K8 intro to first G1 late in 2006 (that's 3 fully years) and they build/test on that future of Phenom CPUs, and then they unganged memory so it could be accessed almost twice as faster with keeping latencies low like in real 128bit mode but that came at price when no easy OCing is possible since Phenom introduction cause no longer easy (for many claimed broken) CPU divider is used for memory frequency but now we have FSB multis like 1/2, 3/5 .... which makes memory always run at max even in PowerNow mode active. Well with detached MC with their own voltage control that doesnt have any affect except extra memory and mch consumption when CPU running in power saving mode and not really needing all of that memory bandwidth. They needed to implement PN for MCH too
IPC isn't much improved in Phenoms (K8L) over old Athlon64 they just get capability to crunch whole 128b SSE in one cycle and got ability to handle much larger pages (needed for server application where lies amd 95% design orientation since K8 introduction) and that's pretty much it. L3 came as quick solution for never developed unified L2 like Intel did in their Core 2 architecture and looking forward to what Intels Nehalems would look like all in one development and cutting r&d budget they never had. And as far as ipc improvement goes more of them was done by ViA in latest Isaiah iteration than AMD has done for it's ipc in the last three years well maybe even 4 after they implemented SSE3 in E3 Venice core
Bulldozer came out from realK10 development which is scraped down somewhere in 2006 and K9 was scraped year or two earlier. So they in fact look what IBM want for their server needs and looking on Sun's Niagara with already some job done in K10. What they really did in K9/K10 was never disclosed. Maybe that memory unganging came from one of that devs. Anyway K10 since it's first glimpses should have been a wholly revamped architecture, as Bulldozer should be, with only virtual support for old x86. And Bulldozer has that x86 nativlly implemented? Anyway HT in bd should resemble MHT like in Niagara (hence all that river codenames in amds bulldozer based server cpus
) not some QuasiSMT like Intel didi in past and latest Atom/Nealem iterations. Again feature needed for server market in architecture that should serve them for next 10 years??? As K7-K8-K8L redesign did.