If you want to know how much your PC or laptop is consuming power, here is the answer.
If you are using normal PC which runs windows operating system and Intel Motherboard, the power consumption by CPU will be around 120 Watt maximum.
The power consumption rate of normal CRT monitor is around 80 Watt and power consumption of small LCD monitor is around 20 Watt only if you keep brightness low. Big LCD monitor (19”) at maximum brightness may consume as much as 100 Watt.
So if your PC consists of normal CPU and average CRT monitor, maximum power consumption rate will be 200 watt. It means if you switch off you PC with monitor for 5 hour, you can save one unit of electricity.
Power consumption rate for average size laptop will be around 50 Watt maximum while laptop is charging and you are using laptop CPU at full capacity with full brightness of screen.
For accurate power consumption rate of any specific PC or laptop, you should go through the specifications of product given in user manual.