Just ordered a new PC with an ATI Radeon 5870 that I plan to use exclusively for gaming. (I love my Mac but I need more muscle for games). My plan was to plug it into my iMac 27" in target mode as an external monitor since the 5870 has a DisplayPort output that I can easily plug into the iMac's mini displayport input via an adapter. But I just read on a couple of forums that this particular series of videocards has some kind of incompatability with iMac. The forum information I saw wasn't that up to date so I was wondering if this issue has been resolved or if I am going to need to return this graphics card. Can anyone shed some light on this issue?