I'd say that either you have a memory stick that's going bad or a HD that's going south.
You need to list your system spec's in your signature so myself and others will know just what hardware you have and please be complete and if OC'd please list CPU speed and VCORE.
Electronic Smoke Signals From my TechnoTeepee
ASUS Crosshair V Formula AM3+ 990FX, 1703 bios
AMD FX 8350 Vishera @ 5162Mhz [21x245] 1.546v 🙂
Water Cooled - Koolance EX2-1055, CPU 370 WB, Idle=22c Load=52c
32Gb G.Skill Sniper ddr3 1600 8G X 4 , 9-9-9-24 @ 1.55v
ASUS HD7970-DC2T-3GD5, Cat 13.5 beta 2, Dell U3011 @ 2560x1600
SanDisk Extreme 120Gb SSD SATA 6Gb, 250Gb SATA 6Gb, 1Tb SATA 6Gb x2
Win 7 Ultimate 64bit, Corsair Obsidian 800D, Corsair HX1000w PSU