Some more Intel "leaked slides" have popped up. If these are true, it looks like the 8 core 20M cache engineering samples won't have a client equivalent anytime soon.
Intel has already said that pricing for the LGA2011 Sandy Bridge-E 4 core will come in around what the 2600K goes for. The non-XE 6 core will supposedly fall within the $550-650 range, and the range topper should fill in the ~$1,000 XE slot.
Intel Desktop Processor: Enthusiast Roadmap
Sandy Bridge-E & Ivy Bridge
X79 LGA2011 6 core
3.3GHz, 15M Cache
3.2GHz, 12M Cache
X79 LGA2011 4 core
3.6GHz, 10M Cache
Intel Desktop Chipset: Roadmap - Consumer Platforms
Intel Z68 Chipset, Intel X79 Chipset, Intel Z77 Chipset, Intel Z75 Chipset, Intel H77 Chipset
Intel Desktop Chipset: Roadmap - Business Platforms
Intel Q77 Chipset, Intel Q75 Chipset, Intel B75 Chipset
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Intel Consumer Desktop Platform Roadmap