quote: 2. You have just proven MY point...Conroe has 4 ALUs! The fewer execution units you have, the more important it is that each is more efficient. Conroe has double the execution units of Netburst, which means that the stalled ALU will not effect the work done to anywhere near the degree that it would on the Netburst architecture. Athlon has 3 execution units, and SMT was found to be more of a hindrance than a help on the Athlon architecture...imagine what the effect would be on 4.
quote: SMT isn't implemented just because of stalls. The more execution units you have, the harder is to keep them fed using only one thread. That's why Power5, which issue 8 instructions and execute 5 per cycle, has SMT