Installing this unit is not plug-and-play. Because it uses a hybrid driver stack (DigiLink + Core Audio/WDM), you must install the "Avid HD 1250 Stepped Controller" software before powering on the unit.
Pro Tip: Use high-quality DB25 snakes. The input impedance on the 1250 is so precise that if you use cheap cables, you will actually hear the microphonics of the cable vibrating against the floor. Avid recommends Mogami Gold or Vovox. avid pro tools hd 1250 exclusive
The HD 1250 card features the distinctive blue "Accel" DSP chips. This generation allowed for more demanding plugin instances (such as high-quality reverbs like TL Space) compared to the earlier non-Accel cards. Installing this unit is not plug-and-play
Setting up the Avid Pro Tools HD 1250 Exclusive is not plug-and-play. To achieve "Exclusive" status, follow this checklist: Setting up the Avid Pro Tools HD 1250