Details Leak on AMD's Upcoming Hexa-Core Processor
Thuban, like Istanbul, will be a monolithic core and will utilize the same 45nm process as its cousin in the server space. In a surprising move, AMD has apparently confirmed that the upcoming processors will be drop-in compatible with AM3, AM2+, and AM2 motherboards. If that turns out to be accurate, Socket AM2/AM2+ owners that first bought boards when 90nm dual-core Athlon 64 X2's were all the rage will be able to upgrade to 45nm hexa-core processors that could well occupy the same power envelope. The Phenom II X6, as it's expected to be known, will reportedly carry 3MB of L2 (512K per core) and a 6MB unified L3 cache. While this has yet to be confirmed, it's probably accurate; the L2/L3 cache configuration on Thuban is identical to both Istanbul and Shanghai. AMD isn't spilling the beans on any of its launch frequencies at this point, but a glance at the company's current product line, plus a little educated guessing, can get us pretty close.
It's not immediately obvious which Intel processors Thuban will target. Based on what we've seen from our quad-core Nehalem vs. Shanghai match-ups, Intel's ultra-high end, hexa-core Gulftown (Core i9) is virtually certain to pummel Thuban in any head-to-head competition. Knowing this, AMD will likely target Thuban against Intel's Core i7 series, and possibly the upper-end Core i5s as well. In such comparisons, the extra two cores will definitely make a difference. HyperThreading is one of the main reasons the Core i7 takes Phenom II to the mat time after time, particularly in SMP-friendly tests. An extra two cores won't work magic, but it'll put the two processors on much more even ground. AMD could theoretically attempt to press Intel's Core i5/i3 processors with lower-clocked Thubans, but the size and complexity of the die (346mm, 904 million transistors) make this unlikely. As with Shanghai, Thuban will have to balance itself on a relatively narrow price/performance tightrope.
We could launch into a discussion of how many people actually need six processors, but that horse done been beat before.