The common cards are Acroloop, Galil, Delta Tau. and all are supported by CNC software, including operator interface, either their own or third party.
You also need a ISA or PCI bus computer that in most cases will run win98SE and up. The advantge is that the card controls the motion control directly and in some cases the I/O, with encoders and motor amplifier control connected directly to the card, independantly of the PC.
The PC just host the card and act as the operator interface. High speed machining is possible because the motion control does not have to depend on the multi-tasking CPU in the windows system.