one way to get the system going with one floppy drive and one hard
disk on a 63 watt power supply is to first disconnect the power from
the floppy drive than turn on the pc, you will notice the hard drive
having a real difficult time getting up to speed, but it manages.
when booting is finished, plug in your floppy drive, now it will work.

(ok I know this is not very user friendly, maybe you are better off
buying a 486-66 with 300 watt power supply or something like that)