Power Consumption on New System

Maybe.

I tried the out put after removing everything (mouse, keyboard, display card)....even then it shows 69 to 70W.

I was wondering what motherboard, RAM and power supply you were using - and how you measure the power draw.
Did you also measure the draw with the CPU under load and the video card in use?

System Spec...

CPU - Celeron 430
Mobo - Asus P5B
Ram - 1GB (2x 512) PC5300
PSU - 520W
Graphic - Asus Geforce 7300SE PCI-Express

To measure the power draw I use an energy cost meter, the one u normally find in electrical shops.

The draw looks normal to me, the psu will pull more power since it needs to compensate for the psu efficiency

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.

I think that the culprit might be the MB. There really isn't anything too high power in the system, and the CPU definitely shouldn't be pulling that much power.

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:


80Plus Standard Bronze Silver Gold
http://www.80plus.org/manu/psu/psu_join.aspx

ENERMAX PRO82+385W 80Plus Bronze 82% efficient @ 90 watts
http://www.80plus.org/manu/psu/psu_reports/SP29_1_ENERM...

Dell has a custom 255watt 80Plus Silver PSU thats over 92% efficient at about what your system would draw;
http://www.80plus.org/manu/psu/psu_reports/SP179_DELL_H...

Yes the PSU was the culprit here. I just tried the PSU from my old PC, 440W PSU. Now its 51W to 55W.

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.