Can you? Yes. You can set the multiplier to whatever you want and never touch the voltage.
Will it be stable? No, it probably won't. It "could" be, but generally speaking if you increase the multiplier you will usually need to increase the voltage as well.
You are not going to get a "yes it's ok" answer on this. Not here.
ANY kind of overclocking, no matter WHAT is is on, requires testing to verify stability, so you are the only person who can answer the question as to whether or not YOU can increase the multi (overclock) without changing voltage and that will be based on doing it, and then testing to see if it is stable. You cannot, EVER, make changes away from the default configuration when it comes to clock speed or voltage, without following that up by testing for stability.
If you are interested in doing that, then this might be a good place to start.
Covering the basics If you found your way here it's likely you are looking for help with basic overclocking. Either that or you're a long time overclocker interested in seeing whether I had any eye opening insights that you may have been lacking. Rest assured, I don't. This is only intended as...
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