Aye, I have heard of this new opteron but have not had any first-hand experience with it so I left it out of my post completely.
I was only referring to 2, 4, 8 and n-Way SMP in my post.
Models 2xx, 4xx, 8xx, etc
The other really cool thing about the Opterons is that they have dedicated Hypertransport buses just to communicate with each other as well as having the integrated memory controller leading to their own dedicated RAM so if you buy enough RAM each opteron in your system can have its own 2, 4, 8 or more GB or RAM all to itself. This RAM is sharable via the CPU to CPU Hypertransport links.
This is really wicked, back in the day this was unheard of -- CPUs in SMP machines had to jump through hoops to talk to each other.
The Opterons also have the bandwidth to offer really FAST access to PCI, PCI-X, PCI-Express and sometimes AGP interfaces on the motherboard and as I mentioned previously some Opteron motherboards even have 2 or more PCI-X buses for TWICE the bandwidth. Tyan for example makes the S2882 board which has 2 x 64bit PCI-X buses each capable of up to 133MHz operation. This is NOT the same as having 2 x 64bit PCI-X slots each bus can work independently has the full bandwidth of a PCI-X bus running at 64bit x 133MHz.
Please do correct me if I mispoke.
Thank you and have a great holiday everybody!