I am new to overclocking and just bought a Raspberry Pi to learn more about computers and run a Java server on. I was wondering: Would overclocking my Raspberry Pi to the "Medium" setting be dangerous? I have heard of the SD cards corrupting and a lot of other bad things that can happen when you overclock, and I am a bit worried about breaking my $35 computer prematurely (I am a cheapskate obviously). Thanks for your help!
Overclocking can cause system stability and SD card issues, but assuming you have a good power supply, moderate amounts of overclocking are normally problem free. If you look at the various overclocking options, the top option mentions that some Pi's have problems at that speed, but you should have no problems with the medium option.
I would suggest backing up your Pi, and then overclock your Pi. If things seem to be working well over time, you may then want to try the next higher setting (again backing up first). Until you reach a speed that causes problems and then back off to the next lowest speed.
On a personal note I am running my Pi's at 950 MHZ without problem.