AMD's E-350 chip isn't a big performer. So it makes sense to put it in a small board.
The Mini-ITX Gigabyte GA-E350N-USB3 is as puny as they come, and yet gives nothing away to Asus's larger E35M1-M PRO when it comes to number crunching.
That said, we wouldn't recommend it for anything but basic computing. It's certainly not a plausible cut-price gaming platform.
For the record, the GA-E350N-USB3 does have a full range of overclocking settings in the BIOS.
However, no doubt due to the E-350 chip's highly integrated architecture, the available frequency headroom amounts to no more than a few hundred MHz.
CPU rendering performance
Video encoding performance
DirectX 10 gaming performance