I have a 27" iMac and a conventional tower PC. I am upgrading the tower with a new GPU because the current HD 5670 (which is NOT TDM compatible it seems) died in a sudden puff. Since I have to buy one anyway, I figured why not a target display mode-friendly one? Will this one work with a M2M Mini-DisplayPort cord going from it the iMac? Code: http://www.amazon.com/HIS-Eyefinity-Mini-DisplayPort-Express-H687F1G2M/dp/B0047N0XBW/ref=pd_rhf_p_t_2 I know there have been several topics about TDM, but I have yet to find a definitive list of OK cards.