Windows does not show true cpu clock speed because it reads the chip default speed. To find the true speed, look in your bios.
Intel Core i7-920 D0 Quad Core CPU 2.80GHz, Overclocked
to 4.0GHz
6GB Corsair XM3 1600MHz DDR3 Triple Channel Memory Kit
Gigabyte GA-X58A-UD3R Motherboard with USB3.0 and SATAIII Support
Titan Fenrir CPU Cooler - (very big and ugly looking, but really does the job)
WARNING: the setting apply to above hardware configuration only - They work fine for me but you use at you own risk.