Last week at Linuxworld there was a stall showing off a dual Opteron server. the motherboard uses PC2100 registered ECC DDR also on the board was a IBM Power CPU running at 90MHz, together with Flash memory holding a Linux micro kernel for BIOS functions and processor failover and replacement. The idea seemed to be that using this, Opterons can be warm rebooted in just a few seconds. But other tasks it looks after include remote administration even when there"s a complete system crash.
Although DDR 333 is not ECC registered yet, the impression he got from this partner was that support for it, and for DDR-II memory, was on the way as well. The machine only used two memory slots out of four, but uses 2GB modules – currently they are apparently very expensive compared to 1GB modules, but the price may come down when this dual Hammer/Opteron launches in February