Magewell capture cards include an onboard crystal oscillator that can provide an independent hardware clock for each capture channel. Each captured video frame will be timestamped in units of 100 nanoseconds. The timestamps of frames from multiple inputs can then be used to synchronize those channels.
Hardware version only changes when the design of the PCB board changes. Updating the hardware helps to optimize the performance or fix known problems. When the users open tickets for technical support on Magwell website, they are required to provide the hardware version.