After yesterday's Intel briefing, it became clear to me that Intel is rushing out to market its 6 cores Dunnington in order to stay competitive, now that AMD is finally shipping its quad-core server chip, Barcelona, delayed at least 6 months because of a bug. Thanks to its Direct Connect architecture, Barcelona would outperform Intel's fastest Xeon in large systems i.e. 4 or more CPUs per machine.

That's why Intel is positioning Dunnington for the 4+ sockets server market what the chip maker refers to EX i.e. expandable scalable/multiprocessor. Dunnington is based on dual core Penryn chips that are glued together. It still lacks the QuickPath Interconnect and the on-board memory controller of Nehalem. But Dunnington sounds like a great quick and cheap (because it reuses the Penryn building blocks) stop-gap solution. And contrary to Pat Gelsinger's opinion, I think Intel realise that they might loose more market share in the high-end server space because of the continous latency of its Core architecture and "poof"... came out with a 6 core!

"When we were defining Dunnington... we were trying to build a cost envelope for the EX server space... So we said we could do several ways. We could be a 4 core part with a really big cache. We could build an 8 core part and have a smaller cache. We basically ran a detail set of workload caracterisation to try to cover a range of performance requirements inside of a certain cost envelope. 6 cores with 16 MB of cache ended up being the sweetspot [for the EX market]", said Gelsinger.

Here's a video of Intel VP Stephen Smith going through the Dunnington presentation:


Finally this is a video of a 4 sockets Dunnington demo to show it's not "vaporware". According to the Intel engineer, Dunnington is a replacement for the current Tigherton and is now under going "fine tuning". Intel will provide complete Dunnington systems for up to 8 CPUs. Beyond that, OEMs like HP, Fujitsu, etc... will have to build custom chipsets, motherboard, etc.