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I lost the power cord of my Western Digital HD Model #: WD5000C037 S/N: WCAPW4090648, now, I can't find what is the right power cord since I don't have the specs, and while looking for it online, I found 2 HD models, pretty close to the one I have but the power cord is different, one of them is 12v 36w 3 amp and the other one is 12 v 36w 2 amp. I just want to know, if I use the wrong one, am I going to burn my HD and loose the info? Thanks in advance!

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As long as the power supply voltage is the same as the old one, it's a DC supply and the plug size and plug polarity are correct, you can always use a power supply that is equal or greater in the amperage it will deliver.

Voltage is the pressure or electromotive force available to push current. Over-voltage will fry stuff connected to it.

Current is the flow capacity that the power supply has. Excess power supply current capacity is unused reserve as the powered device will only pull the current it needs to operate.

If the power supply cannot deliver the current that the device requires and doesn't have overcurrent protection, it will overheat and fry itself.

WDC Book Essentials with USB 2.0 requires a 12Vdc 3.0Amp adapter

WDC Book Essentials Green Ring and Edition 2.0 require 12Vdc 2.0Amp adapters

Basically the older the device, the higher the amperage the spindle motor needs.

The latest USB 3.0 Drives seem to need only 1.5A which would kind kill their power supply if plugged into the old versions that need 3.0A

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Brush up on your physics!

A device basically "pulls" current from the power supply- whereas the power supply "pushes" voltage through the device. That's not an accurate definition in terms of physics, but can help you remember the key principle in this situation.

You can never supply "too much current", the resistance of the hard drive will only allow a certain current for any given voltage. V = IR

That's why you don't see any "Warning! High Current!" signs.

A high current is dangerous- but it can only flow if there is a voltage great enough to overcome the resistance (in this example of the human body).

Likewise, as long as you don't provide too high a voltage (or reverse the polarity), your hard drive will be fine.

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