Many years ago I was using an MCA (multi channel analyzer) ISA card connected to a surface barrier detector to measure beta decay spectra. This stuff basically counts the number of pulses from the detector binning them according to the height of the signal. It had its own acquisition software meant for DOS (the manufacturer provided the sources as well).

The thing is you could operate it under Windows (98) in protected mode, but then you lost statistics. How come? Well, Windows scheduling meant that the MCA only took data while it was allotted time slices, as a result the dead time of the whole setup increased, and you couldn't tell by how much.

Under real mode DOS it took advantage of DOS being almost an RTOS and the program running as a single task and you could be pretty confident about your data.

I don't think using adapters with this sort of cards is a good idea. It's not a matter of drivers, sometimes the old stuff simply doesn't work well when plugged in newer systems because everything has changed and you need to redesign everything. If the old stuff does the job, the OS being unsupported only becomes an insurmountable problem for the folks that consider using an unsupported OS some sort of crime in itself. Well, there's usually more than just an abstract computer being used in such circumstances.