Dropping is fine
I have been running my i5 750 under volted for years(1.04 prime95 stable and 0.8 idle , but it jumps to 1.2-1.216 for anything that uses "turbo" because I have no control over turbo voltage on my board[bit of a shame].).
When you get too low it will blue screen and you know you need to to back up a bit and try an extended test.
Also be careful as sometimes you can drop it too low that the idle states crash.