Sony Vegas Pro 13.0

on sony vegas pro 13.0 (Build 310) when i render a video using main concept HD 1080P internet my monitor shuts off but my computer is still running and i really need to render some videos can anyone please help? my computer: ASRock 980de3/u3s3 Geforce Gtx 750ti AMD fx black edition 8core 3.2ghz...