We have been using R290 cards now for quite some time for a high end four output system to drive video walls. Recently as the walls have scaled in size a VERY nasty anomaly has become apparent in as much as there is a circa 2 frame lag between outputs (cumulative from out put to 4). We have spent weeks trying all Eyefinity settings (also switching Aero on off in Windows) and producing a test video to highlight the issue for full testing. Although toggling the Windows Aero settings changed the effect from inter frame output lag to intra frame output video tearing neither is a solution. This seems to be a fundamental flaw with the card design or the drivers (we have tried most of not all versions of the drivers) so we have eliminated as far as possible every other possibility. We currently find ourselves in the ridiculous position of having to output 4K on a single output and then putting a £1000 Data path image processor inline to do the split! As I say we worked through every Eyefinity setting especially focussing on Vsync related ones to no avail. Any ideas?