I have an Intel Pentium G3258 on and Asus B85M-G motherboard and it was running at 3.6GHz for 6 months or so. All of a sudden, my computer has slowed down and my clock speed has lowered itself down to 0.8Ghz. In the BIOS the target speed is still 3.6Ghz and I haven't changed a single thing. Also, it sometimes pushes up to 1GHz, then back down to 0.8Ghz, if that make a difference.