I couldn’t help but ask why AMD opted to put so much effort into consolidating socket AM2 through 3, but pushed socket 939 customers out into the cold. In order for 939 users to upgrade, they’d need to not only buy a new CPU, but also a new motherboard and new memory - pushing the price out of reach for next to no performance benefit. With Intel’s Core microarchitecture following so close after the relatively lacklustre socket AM2 launch, I’m pretty sure most enthusiasts either didn’t upgrade, or upgraded to a system based on Intel’s new CPU architecture.
I was greeted by some rather puzzled looks from AMD’s execs, and I got a two part answer to my question. The first came from Dave Everitt, EMEA Product and Platforms Manager at AMD. He said that “in order to get the bandwidth required for HyperTransport 3.0, we needed a few more pins. The way we’d pinned it out [in the past] meant that was how it turned out to be.”
On its own, that was a pretty feasible answer. I don’t quite know how far out AMD was working on DDR3, but I’ll assume that it wasn’t before the socket 939 pin layout had already been finalised.