Users of systems running Core i7 processors in the LGA2011 package and X79 chipset motherboards will find that their GeForce GTX 680 will not run at PCI-Express 3.0 x16 mode, using launch drivers. This is because NVIDIA decided against implementing Gen 3.0 support for the new GPU on X79/SNB-E systems, at the very last moment. Pre-launch drivers, including the driver that ships on discs with the graphics cards, will let the GPU run at Gen 3.0 mode on some X79/SNB-E systems, however the post-launch stable drivers (such as GeForce 301.10 WHQL), won't. The specifications page of GeForce GTX 680 on GeForce.com has been updated to mention this: Sources in the PC motherboard industry we spoke with, confirmed this change. PCI-Express 3.0 x16, for now, might only run on upcoming "Ivy Bridge" Core systems, running on motherboards with PCI-Express 3.0 compliant components. NVIDIA could be working to fix the issue. Update 3/23, 21:56 NVIDIA courteously responded to our article, with a statement. Here's the statement verbatim: This statement confirms our assertions made in the article. NVIDIA's statement on the GeForce.com product page originally formed the basis of this article, which we pasted verbatim, while preparing the article. Motherboard manufacturers have extensively marketed their LGA2011 products as natively supporting PCI-Express Gen 3.0 (8 GT/s). What's more, the datasheet of Intel Core i7 LGA2011 processors (refer 1.2.2) clearly mentions the PCI-Express root complex as supporting 8 GT/s. AMD Southern Islands GPUs have supported PCI-Express Gen 3.0 on LGA2011 platforms since day one.