AMD sockets

This is more to help me remember than a really sueful article for anyone else.

There are three AMD sockets around these days:

Socket A
Original socket, used for older AMD chips like Thunderbird through to Athlon 2800+
Socket 754
First socket that could handle Athlon64 CPUs.
Now relegated to low-end AMD CPUs like the Sempron, which are rated these days around 3000-3100+.
Has only a single-channel memory controller.
Socket 939
Current main socket, used in high-end Athlon64 CPUs.
I guess it has a dual-channel memory controller?

Ah, how I miss the days of there being one and only one socket.

I am completely lost on the Intel side of things.
How many incompatible sockets are there now for all the various flavours of Pentium 4?