The performance of devices like smartphones and tablets (usually ARM-based) isn't easy to compare versus PCs, but a new generation of benchmarks is making this task a lot easier. The performance of mobile devices has increased significantly in recent years, and one question that likely lingers in your mind is how fast your phone is versus your desktop PC. AnandTech published a new article that addresses this topic, the site brought a series of modern smartphones and tablets to the testbench and compared their graphics performance with those of NVIDIA GPUs from 2004 - 2007. You can check out the article over here, the conclusion is that the current crop of high-end ultra mobile devices can deliver GPU performance similar to that of mid to high-end GPUs from 2006.
gh-end ultra mobile devices can deliver GPU performance similar to that of mid to high-end GPUs from 2006. The caveat there is that we have to be talking about performance in workloads that don't have the same memory bandwidth demands as the games from that same era. While compute power has definitely kept up (as has memory capacity), memory bandwidth is no where near as good as it was on even low end to mainstream cards from that time period. For these ultra mobile devices to really shine as gaming devices, it will take a combination of further increasing compute as well as significantly enhancing memory bandwidth. Apple (and now companies like Samsung as well) has been steadily increasing memory bandwidth on its mobile SoCs for the past few generations, but it will need to do more. I suspect the mobile SoC vendors will take a page from the console folks and/or Intel and begin looking at embedded/stacked DRAM options over the coming years to address this problem.