Right now, the release of AMD's new dual-Athlon chipset seems more like a technology demonstration rather than a full-blown product release. We have learned that dual-AthlonMP is performing very well indeed, but as long as AMD doesn't supply AthlonMP at high enough clock speeds, Intel's Xeon solution has a clear performance advantage.
The high cost of the Tyan K7 Thunder cannot be equalized by the relatively low costs of AthlonMP. Right now dual AthlonMP systems are only interesting for server and workstation setups, where the system price is not considered important. However, even though AthlonMP is significantly cheaper than its Intel Xeon counterpart, it doesn't make a large difference once you look at the price of a complete server or workstation system.
We have seen that AthlonMP benefits more from dual-processor operation than Xeon, so that AthlonMP has a good chance to catch up and even overtake dual Xeon once AMD supplies AthlonMP processors at higher clock speeds. However, right now I wouldn't see how AMD would be able to attract a reasonable amount of customers with dual Xeon beating AthlonMP in the majority of benchmarks.
Home users will have to wait for inexpensive motherboard designs before they can afford their own dual AthlonMP system.
The performance increase from Athlon with Thunderbird core to Athlon with Palomino core is with 2-8% not quite what we would have liked to see. It is one reason more why users who want to run Athlon in single configuration should wait until the official Athlon processors with Palomino core for single-CPU operation become available, rather than spend too much money on an AthlonMP now.
As far as our testing is concerned, we didn't see any issues with dual-operated Athlon processors based on the Thunderbird core. Those processors feature the same SMP-capabilities as Palomino, even if AMD doesn't want us to believe it. However, no Thunderbird was or will ever be validated for dual-operation, which basically means that AMD doesn't take any responsibility if you should run into trouble. The story looks very similar to the good old Celeron SMP-situation of a few years ago. Intel claimed that Celeron wouldn't support SMP, but in actual fact it did. It's all politics, my friends, and wouldn't the world be a boring place without it?