You are asking advice about O.C. and have not provided and hardware specs. MB, Memory, CPU cooler, PSU, case, case cooling...nothing. So to give you advice is not possible. The article takes you through the steps and gives examples. Each set of changes must be tested for stability. Not all cpu of the same model are the same. Some O.C. better some not so good. Sample variability. Since you have no idea what you are doing I would say no it is not safe.