Hello, I have AMD RADEON HD 5770 1GB and i have changed my motherboard to GA-MA785GT-UD3H and I have 4gb of ram, and AMD II X6 1055T and the problem is, while I'm gaming after a while red screen appears, and sometimes white screen and I have to restart my PC. Could it be to power supply? Because I have changed cases and put my components in it but I haven't put my power supplie because it is 400W and the other one is 400W too