Hi,

The power cables for hard drives and cd-rom drives have both 5 volts and =
12=20
volts. CD-ROM for example needs 1 amp @ 12 volts peak. (Excluding special=
=20
parts such as the laptop drive you mentioned).

I'd guess the 12 volts is to power motors inside the drives, etc, while t=
he 5=20
volts is for the rest.

The 5 volts should be kept as stable as possible, but I don't think the 1=
2=20
volts is as crucial (assuming a peak voltage of about 14.2 volts while=20
charging, and 11.8 volts for a basically dead battery).=20

The serial ports might use the 12 volts directly, but you can have a look=
 if=20
they use some IC's similar to the MAX ones.

Of course - don't try it with your new GeForce 4 :-) Have a look around, =
maybe=20
probe some voltages while running off a normal supply.=20

Don't take just my word for it! I would hate to hear it didn't work!

If you build the power supply yourself completely, make it big enough to =
power=20
the whole system (dozens of Watts for a Athlon/P3+ system with CD, drives=
,=20
etc).

Goodluck, and let us know how it turns out!
Best wishes
Dennis

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