Bit Tech writes the 45nm Yorkfield quad-core processors from Intel are still not widely available. The site heard Intel is having capacity problems, it's not a problem with the yields but it's likely because Intel is taking care of the more lucrative server market first:
Demand for these products is exceedingly high, we’re told, and Intel is aware of the problems with availability of its desktop chips. Indeed, availability of the 45nm Harpertown-based Xeon chips looks to be pretty good, although interestingly the 2.5GHz Xeon 5320 parts are not available. The Xeon 5410 and 5430 (2.33GHz and 2.67GHz) are available, as are the 2.83GHz and 3.00GHz 5440 and 5450 chips.
This suggests that there aren’t issues with the yield, but Intel is taking care of the more lucrative server market first. After all, the power savings as a result of moving an entire data centre to 45nm processors would be significant. The question remains then, when will we see Intel’s quad-core 45nm processors widely available on the market?
Intel is apparently working to free up some fab space to deliver 45nm desktop quad-core processors to the market, but it may take days—or even weeks—for that to filter out onto the market.