no solder v5 v6 the same?

[jokerswild]

actually my buddy ordered specifacly a version 5 chip. so he got it yesterday and i put it in for him and low and behold it didnt work. i noticed the different configuration of the contacts so i flipped over the ribbon cable and it didnt work either so then i looked at his mod box and it sez v6. so now i tell him he has the wrong chip, take it out and put the ribbon cable in as it was before any modding done. still does not power on.
is his ps2 screwed now?