vb_master wrote:What if he has a Sharp TSOP, then he has to solder an extra wire, right?
yes... in case of the sharp he will have to solder that extra wire, put the jumper on the back, boot the installer and when ready to flash put the flash enable point on the front and the flash...
in other words look at this pic...

step by step...
1- put a line of solder on the points that are on the blue circle (right side of pic, back side of the mobo)
2- put a wire on those points of the mobo (right side of pic, back side of the mobo
3- put one wire on the Point A and one wire on the Point B like 6" each (left side of the pic, front side of the mobo)
4- Boot the Installer and when you are ready to select flash on the menu join the A and B wires to enable the flash... the flash and wait... thats all
if you plase all the jumper before power the xbox it will simply dont boot
you can also make the 2 bios trick and place the sharp jumper... put the S2 to Off and turn on when ready to flash... thats all... but remember that the console will not boot on "sharps" if the enabler are on when you turn it on