So im building a new computer with a thermaltake black widow 850w PSU. Whenever i start the computer i usually see "cmos settings wrong" at start up and then i lose video and the computer just sits there running on a black screen. I swapped in my 850w corsair PSU and the computer starts up and runs fine with no problems. I installed windows, shut the computer down swapped the thermaltake PSU back in and i get the same cmos error and lose video as before. I have returned the power supply twice and gotten a new one twice so i dont think that all 3 PSU's are faulty. Im am not new to computers and building them but i am by no means an expert and i am lost at the moment. I have swapped out all other parts of the computer with known working ones and it is no doubt the power supply but i do not understand why. I also swapped the thermal take into my know working system that i am on now and it also shows the same problem of no video on start. Thank you in advance for any help!