Traders are making record bets against AMD (AMD)

Betting against AMD this year has been unprofitable, but that's not stopping investors from jumping on the trade. 
Short interest, or bets that the semiconductor manufacturer's stock price will fall, rose to an all-time high this week, according to the financial-analytics provider S3 Partners. The shares sold short rose to 159 million shares, or an estimated 18% of those available for trading.
That leaves plenty of room for those who still w