Just be aware that even real bench isn't guaranteeing stability. You want the lowest vcore you can run that doesn't crash. If you find it's stable, you could lower your vcore a little, perhaps 1.28v and see if you're still stable. Fortunately most instability will reveal itself fairly quickly so you don't have to run it for hours over and over. Ideally you want to get through a few hours of real bench without temps over the mid 80s or so. if 1.3 doesn't work, try 1.33 maybe You could start higher and work down towards a lower figure. Work in small increments and keep it under 1.4v.

If you crash you need to add a little voltage. You have to balance more voltage for stability but higher temps Vs lower temps but less voltage increasing the chance of crashes. Something like Core temp is good for this. Run realbench for a little while and see if it crashes.

So say we're in windows having set vcore to 1.3v and we're at 4.7ghz. At reasonable levels (rather than maxing it), with reasonable vcore set in bios that's not something to worry about. LLC will iron out that drop a little, but at the expense of slightly higher voltage when idle, and little spikes of voltage when transitioning between load and idle. Do something stressful and it drops to say 1.22, and that's isn't enough for stability on that work load. So if you set 1.3v, you might be fine in windows and browsing etc. If you're monitoring your CPU stats during stress tests you'll see that under full load the voltage your chip receives actually drops. General guidance if you're using LLC is to go with level 4 out of 7 or thereabouts. Can't comment on Asrock, but it tends to have levels that you can apply. On Asus boards it's under DIGI VRM management. Somewhere in bios as well you'll see something called loadline calibration. For 4.7 I'd start with a vcore of 1.3v and see how you go. That's the number you'll need to get right to get 4.7ghz or what have you stable. Set it to 47 if that's what you're going for. The quick and dirty however is basically: Dig around in your bios and look for your CPU ratio or multiplier. Great link posted by the other guy, give that a read. Real Bench is probably your best bet to test stability. Temperatures were probably in the mid 80s during something like Real Bench. I was able to run 4.8ghz on something like 1.37v if I recall correctly.

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