Yeah likely it does have 4 screws, but if you want to replace the graphics card you are going to have to figure out how to open the case anyway. Finding out the PSU's specs is really the first thing you should do, IMO, so props for asking. Most likely, a 700W PSU should be able to handle it, but, call me a skeptic, but I have seen 750W power supplies with only 400W on the 12v rail...no good.