Sorry for being vague.So I'm using a Palit GTX 970, connected to the Akitio Thunder2 with a powered molex riser. I'm not using the Akitio PSU at all, only my 500W PSU. I believe my hardware setup is correct because it works perfectly on Mac OS X Yosemite. However it does not work for Windows 8.1. I followed the instructions and installed Windows 8.1 using Bootcamp. Updated everything. When I boot Windows with my eGPU plugged in, the internal display works but the external display receives no signal (before installing NVIDIA driver).Then I attempted to install the latest NVIDIA Driver for GTX 970 on my internal display with the eGPU plugged in. The NVIDIA Driver installer detects the GTX 970 and allows me to proceed with installing the driver. The driver was installed with no problems. But when I reboot into Windows, both the internal and external displays are black. Tried to boot many times with eGPU plugged in before the chime booting sound. Same results.Tried to plug in the eGPU when I hear the booting sound. Same results.Tried to plug in the eGPU at the boot disk selection. Same results.Everything works normal with eGPU off.I tried to reinstall Windows many times but the same issue prevails.