First of all, almost nobody overclocks a server. The risks are just too great.
The advantage of overclocking is faster processing.
But there are some serious disadvantages. Just a sample:
1. Loss of warranty. Most hardware manufacturers will not homor warranty on a system that they know has been overclocked.
2. Shortened component life. Any significant level of overclocking will almost certainly shorten the life of one or more components. There is no way of knowing how much. Of course the system may become obsolete before that happens.
3. System instability. This could mean application or system failures. Or worse, the system may silently corrupt your valuable data.
There is no way of knowing ahead of time how far any given system can be overclocked. Experimentation is the only way to tell.
Overclocking means operating the system outside the bounds set by the manufacturer. This is serious business. It should only be attempted by someone who fully understands what they are doing.
If you wish to experiment with overclocking do so on an old system you do not care about. Never experiment on a server with valuable data.
