Okay, the second story was "Second Chance" by WhiteWolf (and there was a sequel "Choices"), that sadly does not appear to be online anywhere anymore. If you're interested in reading it, let me know and I'll forward it to you.

I stumbled across one other, but sadly I only have the first chapter and no author name (excuse me while I go whack myself upside the head for being an idiot), where it turns out there never was a chip at all... it was all in his mind, so to speak. It's old enough that it's not showing up anywhere online with any of the keywords I've tried.