two x-fis both broken? both vista?

hi, i have a x-fi extreme music sound card, ive had it months and im REALLY please with it, the quality is truly hi-fi level, but everything was well with xp mce2005, but with a new install of vista ultimate 32, after a few weeks it broken stopped working altogether, i downloaded the latest drivers and even vista itself downloaded the driver update for me, the card is detected within windows as a multimedia audio controller as you'd expect but the driver installation fails half way through, i put the card in another pc running mce2005 and that had the same problem, i presumed the card faulty and returned it for a new one, getting the new card home i installed it in my vista pc in place of the old one, and installed it, it worked fine, btw i know about the vista hal removal, this isnt the issue, again after a week in the machine it died too, same problem i turn the pc on and windows finds "new" hardware, my x-fi, then the drivers fail and it all goes down hill from there, i have no idea why this is happening to me, i build computers by both hobby and trade and im quite experianced but im stumped here, so guys its over to you,..... thankyou in advance :major i-CONICA :major

 

to add, i thought maybe, (unlikely) the 3.3v supplied on the pci slot was to high and was damaging the card, because the motherboard ASUS A8N32-SLI DELUXE is heavily overclocked and overvolted, but this doesnt explain why the cards have only done this in vista and not xp?......... :major i-CONICA :major

 

hey, this is the only thread i ever started that no-one has replied to, hasnt anyone got any ideas whats causing this problem, hey im open to guess', come on guys help me out? :major i-CONICA :major