when I go to avaliable modes, I see that I can get up to 165 hz, but when I go to select the resolution the 165 hz isn't there. when I try to set a custom resolution, as 165hz, I doesn't work. Please help me.
There is a big difference between the modes that the monitor says it will support and the modes that will actually work. If you are not able to use the highest possible mode, I would suggest that you start by getting a better quality monitor cable (more than 90% of the time, it *is* the cable that is at fault).