If you were one of the early adopters of the X2, you may remember that a hotfix was needed for Windows to avoid serious performance issues in Windows XP. Now, on the Intel side, an eerily similar scenario is panning out. A “Critical” fix for owners of several models of Core 2 processors has been released. In mid-June, a microcode update for Core processors was made available for download.
What is interesting is the lack of information Microsoft released about the fix, which many sites noticed. Coupled with the lack of fanfare for a “reliability” update, it has made many curious. It seems that even Dell was concerned about this issue, enough to warrant “urgent” BIOS and microcode updates.
If you are using an AMD processor or are not using Windows, you aren't affected by this flaw. It seems to affect several models of Core 2, including the Duo E4000/E6000, Quad Q6600, Xtreme QX6800, QX6700 and QX6800. While the fix has been published for a few weeks now, very little has been released regarding it. If you are using a Core 2 CPU and Windows, you should definitely check in on the update.