I'm running Windows 7 with this CPU: Intel Core i5-2500K Sandy Bridge 3.3GHz 6MB Cache, LGA 1155. Windows Upgrade Assistant reports that I cannot upgrade to Windows 8.1 because the CPU doesn't support NX. According to Coreinfo, NX is supported, and in the BIOS>CPU, NX is enabled. I've attached a screen shot of the Coreinfo report. Please advise.