the replacement cable may stop your xbox from catching on fire but it won't fix ANYTHING.
the problem in the V1.0 xboxes is that the power socket is not secured, so it wobbles a bit every time you plug it in. this leads to the solder joints failing and an electrical arc occurring at those broken joints. this CAN cause an electrical fire. my friends xbox had a hole burned in to the board from that happening and he had the replacement cable...
luckily i could fix it with a bit of solder, some wire and lots of epoxy to stop the socket from moving
i think a similar thing happened to the guy who made this forum