U2312HM, green tint on right 1/4 of screen

I had this monitor replaced about a year ago for the same reason, and it has appeared again on the new monitor. How can I get this replaced, again? Unplugging it and plugging it back in doesn't help. Shutting the monitor off and turning it back on helps for about 1 minute. I've used a new DVI cable with the same result, on a different computer.

Thanks,
Bao