Download Prime95 and Hardware Monitor (I like HW Monitor others might recommend SpeedFan). Enter BIOS and increase the CPU multiplier by 1. (ie from 14-15x). Save and exit. If it POSTs, increase it by 1 more. Save and exit. Continue to do so until it doesn't POST. Reduce by 1 until it POSTs. Let it startup, open up Prime95 and HWMonitor or SpeedFan depending on what you decide. Let Prime95 run for at least 2 hours while monitoring temperatures through HWM or SF. CPU temp should not exceed 60c. If it does, immediately end Prime95 and shut down. Decrease multiplier by 1. Rerun tests while monitoring temps. ~55c under load is safe given you have quality, adequate thermal compound and adequate airflow in the case.
Older versions might look something like this... http://i.imgur.com/LZeLX.gif Nowadays, they're graphics that look pretty similar to the outside of the motherboard box. 990FXA-UD3 written in big bold letters, white background, some features of the mobo listed, etc. It's the screen at which the commands to get into the BIOS must be struck.
Basically, yes. You still have to run the tests and be sure you're not overheating. Technically, you would want to run the tests each time you increase it so as to be sure you're not damaging the processor. You can, instead, set the CPU temp limitations in the BIOS so that it won't run if it gets beyond ~60c.