Hi,
I have a fairly poor 2500K compared to some so need more vCore than is usual. However, I'm still happily at 4.6ghz and have been for many many months without issue.
I haven't got the exact details in front of me (on another PC) but for 4.6 I set ~1.3 vCore in the BIOS. However, this equates to a little over 1.4 vCore draw under heavy IBT load. ~1.35 vCore under the lighter Prime95 stress test and ~1.32 vCore tops in heavy gaming (I play a few CPU intensive games)
If your vCore figures are actually draw measured when under load then I'd say they are very very good. If they are purely what you're setting in the BIOS then be very careful as your actual draw under load will likely be a lot higher. CPU-z works for monitoring actual draw. Using various LLC settings (depending on the options your mobo offers) can effect this draw under load either way. I've seen people who've been happy with their "4.5ghz + at 1.25 vCore" only to find they're actually pulling over 1.4 vCore under load.
Final point. One thing worth checking for is stability under partial load. What I mean is while stressing all four cores using IBT or Prime95 might be perfectly stable, stressing just one, two or three cores may not be. Most games, even fairly demanding ones, regularly only push one or two cores with the other two only lightly loaded. I've had direct experience of this myself and with friends machines. I.e. they could bench for 24hrs under high load perfectly stable, then they'd fire up a game and it'd die within minutes. The partial load stress tests (limiting the cores IBT or Prime95 run on) highlight these issues very quickly. For me a bump in LLC was needed to fix this, odd considering overall the system was less stressed - but sorta makes sense if you think about it.
Sandy Bridge overclocking is generally fairly straight-forward and, up to about 4.5ghz or there abouts, you can often get away with just altering the multiplier and vCore. After this point (in my experience) you need to start tweaking LLC and other settings to ensure proper stability. It's a fun process so don't be put off, just remember to take baby steps, adjust ONE thing at a time, monitor heat carefully to ensure you're as safe as possible.
Note: LLC on auto works, however it tends to be overly aggressive in my experience (3 separate SB motherboards) so learning the best manual setting is preferable.
Cheers,
Scoob.
