I DO NOT RECOMMEND OR ADVISE GOING OVER 1.4v ON ANY SYSTEM UNLESS YOU KNOW WHAT YOU ARE DOING. THIS IS NOT A MOTHERBOARD GUIDE EITHER, GO TO THE TOMSHARDWARE MOTHERBOARD GUIDE FOR THAT.
1000w power supply
A motherboard with an OC chipset
Liquid Cooling System
All CPUs should stay under 70-75C under load to ensure a safe, long, and cool operation.
I say around 40-45C idle is a little high but it is fine.
Overclocking is the action of changing the clock rate of any electronic with a clock in it, and making it faster. The most popular application is in computers, as this is why you would be reading this. There are two types of overclocking, BCLK overclocking, and multiplier overclocking.
If you are BCLK overclocking, your CPU will not have an unlocked multiplier, it is much harder to achieve a stable overclock with BCLK overclocking, as you are changing the base clock on all of the items on a clock in your computer. Those include: The CPU, the NB Chipset, and the RAM.
You can achieve a stable overclock with BCLK overclocking though. The way you do it is you have to adjust all of the voltages on all of the effected items.
You have a computer with a BCLK of 100MHz, you turn up the BCLK to 125MHz. That will change your RAM from DDR3 1600 to DDR3 2000, which means you will have to turn up the voltage because it will not be stable at the stock voltages. The CPU has a multiplier of 27, that will also change the clock rate to 3.375GHz. You will also have to up the voltage on that too. You will not have a stable system as easily as the Multiplier OCing.
If you are multiplier overclocking, I will assume you have an i5-4690k or FX-6 or FX-8 series CPU. It is easy to have a good, stable overclock on a multiplier. You start with a CPU and you only change the CPU's clock rate, which helps with system stability. You have to up the voltage still, but it is a lot better than BCLK Overclocking.
You have a computer with a CPU that has a 34x Multiplier, a 3.4GHz clock, and a 100MHz BCLK, you turn up the multiplier to 40x, a 4.0GHz clock, the system will be producing more heat, and consuming more volts, you will need a good cooler for both the BCLK overclocking and the Multiplier overclocking.