Some things (games, programs, benchmarks, etc.) like fast memory, others prefer as tight of timings as possible. I usually try for fairly tight timings with as much frequency as possible,
I suggest trying to use XMP settings first and then you can worry about manual settings later. I ran at the XMP settings for a couple months before I felt compelled to try more.
If you have a single stick of 16GB, you are missing out on dual channel memory which means you're losing a lot of performance. If you wanted 16GB total, you should have got 2X8GB. Since you already have the 16GB module, you might consider getting another one like it to match.
I see a lot of people are confused about overclocking RAM. I will start a new thread that might help.