I got my retina MBP this week and have been waiting for my thunderbolt to DVI adapters to get here so I can hook them up to my external displays. In the meantime I am using an older HDMI to DVI cable I got from Best Buy a few years ago. This is the cable (http://www.amazon.com/Dynex-1080p-DVI-D-Single-Cable/dp/B0013NDHNU) Anyways...I've noticed every once in a while the monitor I am using will sometimes go blank for a second and then back. It doesn't happen very often, but I'm not sure if this has to do with the cable, monitor, or my rMBP. I have two of the exact same HDMI to DVI cables and I've noticed it happen with both of them. It might happen once an hour and even though it may be only a second, it's enough for me to notice. Do you think it's a problem with the rMBP or something else? Would love to hear your opinions. Update, as of posting this it still hasn't happened again. So it definitely is very infrequent. What do you guys think? Thanks!