Power Supply Reccommendation
GTX-1050 2GB  - Minimum 300W+
GTX-1050ti 4GB - Minimum 300W+
GTX-1060 6GB - Minimum 400W+ (VR Capable)
GTX-1070 8GB - Minimum 500W+ (VR+SLI Capable)
GTX-1070ti 8GB - Minimum 500W+ (VR+SLI Capable)
GTX-1080 8GB - Minimum 500W+ (VR+SLI Capable)
GTX-1080ti 11GB - Minimum 600W+ (VR+SLI Capable)
 
If you are choosing to use multiple GPUs you will need to increase the power supply according and you also need an SLI Bridge to connect Dual GPUS