Information is sketchy still, but apparently Intel is cutting revenue forecasts over this chipset flaw due to it's seriousness. I'm still digging to find info on the flaw itself.
The error affects its Intel 6 series chipset, the company said, and it is prompting it to hold all shipments. The design error will reduce revenue by about $300 million.
Update: Thanks to Caveman_jim for this info:
As part of ongoing quality assurance, Intel Corporation has discovered a design issue in a recently released support chip, the Intel® 6 Series, code-named Cougar Point, and has implemented a silicon fix. In some cases, the Serial-ATA (SATA) ports within the chipsets may degrade over time, potentially impacting the performance or functionality of SATA-linked devices such as hard disk drives and DVD-drives. The chipset is utilized in PCs with Intel’s latest Second Generation Intel Core processors, code-named Sandy Bridge. Intel has stopped shipment of the affected support chip from its factories. Intel has corrected the design issue, and has begun manufacturing a new version of the support chip which will resolve the issue. The Sandy Bridge microprocessor is unaffected and no other products are affected by this issue.
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