Why cant amd do hyperthreading?

I dont know if they can't or wont, but the I-7 hyperthreading 3.0 sounds like it rocks, so why wont amd do it?

IMO, and it's just an opinion, it's because of pride & the need to distinguish themselves from Intel. According to AMD, HT only nets +20% to - 10% performance gain (which may be their estimate on Shanghai/P2, not necessarily the same for Intel CPUs). So officially they think it's not worth it. Intel, OTOH, had HT on P4 (albeit not too good an implementation), so they have better first-hand experience with it. And their data shows as much as IIRC 30% gain on some lightly-loaded, multi-threaded apps, at the expense of <5% extra transistors.

So once you get past the marketing hyperbole on both sides, AMD might actually consider it for Bulldozer when it comes out in 2012 or whenever.

I also think Intel's approach - HT for multi-threaded apps and turbo-boost for single/low threaded apps, makes a lot of sense and added value for their customers. However essentially AMD has something similar to turbo, with their ACC app that can up the clock speed, although not automatically as with Intel IIRC.

I think that's HTT 3.0 - hypertransport 3.0. HTT is just the high-speed bus connecting the cores, like Intel's QPI on Nehalem.

Just wondering, because in my opinion amd always designed better cpu's up until the fiasco that was the phenom 1, even though the original core 2 processors were better performers, the amd x2 series was still better designed. The intel I-7 is just awesome though, no amd fanboy can argue that, thats why i figure amd better pull a trick(like hperthreading) out of their hat.