What disturbs me is that techs now existing for so long, whatever the name, like Crossfire and SLI, still give so many hassles. BTW solving synchronization problems has been done even longer, since physical and virtual parallel machines exist, yes, the difference is that parallel GPUs have less time to do it without their main job, producing a frame, goes bad, but they also have to do a more streamlined and predictable job than generic ones done by CPUs.