I completed the build of my new system yesterday. I wanted to use it as a home server so I wen for an Intel Celeron 430 CPU which according to the specs draws only 35 W. Other than the CPU the system got 1 PCI express card and 1 PATA drive with 40GB. With this setting it draws around 70W of energy. Is this normal?
The 70W draw at the wall socket means the PSU is providing 56watts of DC power to your hardware if the PSU is 80% efficient at the 75watt draw. It could be as low as 70% efficient meaning your hardware is using 49 watts of DC power.
Will getting a low watt PSU is going to make any difference?. Its not for gaming or day to day use. The graphic card is with passive cooling and there won't be any more extra devices added other than few more hard disks, mostly 2 more.
Not necessarily - only getting a PSU thats higher efficiency at the low wattage draw of your system will reduce your draw from the socket.
You have a better chance of finding a low wattage PSU that has higher efficiency in the low range your system will use just because a PSUs best efficiency is in the middle of the power band. Example:
honestly i wouldn't even be concerned about it pulling 70W of power. You should be more concerned about your car. Every horsepower in you car is 755 watts of power. so, a 200 HP car consumes 151000 watts of power. And that is only 200 HP. And car are also EXTREMELY inefficient.