The MaxxPI² 16MB calculation test showed a small 3% performance margin standing between the fastest and slowest P55 motherboards. The Asrock P55 Extreme was the weakest link here with all other motherboards delivering roughly the same performance.
Interestingly the MaxxPI² CPU Mips and FPU Flops tests strongly favor the Asrock P55 Extreme whereas previous tests have not. Although the margins were minimal, the Asrock board appeared to have a slight performance advantage.
Again it is the Asrock P55 Extreme that stands out amongst the pack delivering the best MaxxPI² Prime results, even if by minimal margins.