There seems to be two general technological thrusts behind Opteron. The chip can run 32- and 64-bit software, but it also reduces memory latency. It seems like a lot of the bang for the buck, at least initially, will come in reduced latency.

If you look at the product features of Opteron and compare it with what's in the market today, there are generally three new features. One is the 64-bit extension to x86. No. 2 is the integration of the memory controller onto the microprocessor silicon, which of course is a good thing for memory latency, and hence a very good thing for performance. Memory latency is a barrier to better system performance.

The third element is the creation of Hypertransport, which in particular is relevant in servers. Hypertransport essentially allows you to build systems that scale very well. As you add processors to the system, you also pick up memory capacity and memory bandwidth.

Article