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electric current of Motherboard (approximately)? only motherboard, processor and ram, no HDD, PCI, PCIe, DVD Drive? Answered

I made a plan to make the battery for the motherboard, I want to know, how much current is needed.
I asks this because I have broken mutimeter.
and i have a plan to buy MSI
785GM-P45, amd athlon II x2 245


If I am not wrong the voltage of the motherboard should be between 3.3 and 5 volts. You may have to use a multimeter and "piggyback" the motherboard power connector with the multimeter probes. Before you attempt to do this you need a diagram with the polarity of every cable in such connector(s).

One major limiting factor will be the processor you plan to use. Your chosen motherboard has an AM3 socket, which fits a pretty wide range of CPUs, with a pretty wide range of power draw.

An AM3 Sempron might only draw 45 W, while an AM3 Opteron might draw 115 W. (This came from Wikipedia specs and Googling 'CPU tdp' for a particular CPU).

Unless you're just really stuck on this board and/or processor type, you might be as well off to look at PCs intended for automotive usage. Or at least consider a pre-built power supply to convert your battery voltage into the necessary 5 V and 12 V lines for the motherboard.


7 years ago

These are the specifications of a power supply of a motherboard pentiun 4, I don't know if your card is similar; still doing a calculation can be traced back to an average and maximum absorption of your possible battery.


Do you plan to regulate the power?


Exact draw depends on the motherboard. If you're buying a mb for the purpose, specs should be available from the mfgr. Generally, faster systems need more power.

thanks for quick reply.

does it more than 4 ampere ? (for standard motherboard ex : MSI 785GM-P45)