GhostX9 writes "Tom's Hardware just published a detailed look at the Intel Atom Z2760 in the Acer Iconia W510 and compared it to the NVIDIA Tegra 3 in the Microsoft Surface. They break it down and demonstrate how the full Windows 8 tablet outperforms the Windows RT machine in power consumption. They break down power consumption to include the role of the CPU, GPU, memory controller and display. Anandtech is also reporting similar findings, but only reports CPU and GPU utilization."
Despite repeated claims that x86 is beating ARM here, they look neck and neck. Assuming you can make a meaningful comparison.