That may be the case, but who's to say he wasn't talking to a higher level engineer? The fact is, Intel states that 1.5v is safe. Unless you believe that you are smarter than Intel's engineers, I'd accept that voltage as the "max safe limit."
I'd personally never run it that high, but Intel states that it's safe.
And yes, Intel and AMD both state their max recommended voltages. For AMD's 45nm chips, it's usually 1.55v. They know their chips are being overclocked, and they actually encourage it. Why else would AMD have Black Editions, and Intel have the K versions with unlocked multipliers? Surely not to overclock?!
I realise that all i'm about to say contradicts my previous statement about overclocking not being supported... its late.
Intel has a new system to make overclocking easier, where everything is set to auto and the CPU "selects" a voltage from the "VID Table" (side note: im begining to believe VID stands for Voltage Identifier), based upon what multiplier is chosen, each VID Table is individually programmed for each CPU, Vdroop is as "Wumpus" stated, when the Amperage increases, the safe voltage is reduced, so the CPU needs to reduce the voltage to stay within safe limits.
While 1.52v might be safe at idle, it is most likely not safe under heavy load at higher frequencies (increased amperage) so it droops to 1.4v.
This is all speculation on my part [based on many hours of research i have done into overclocking sandybridge] as i have no firsthand knowledge.
Xroo, a suggestion for the degredation test, perhaps we could test the advice given via webchat:
~ lowest stable Vcore at 4.5ghz as degradation basis
~ Both CPU's at 1.52v Vcore (or 1.5v to be within margin of error)
~ 5ghz Overclock
~ Identical cooling setups (preferably water)
~ Test benches to be identical (Mobo, and so forth)
~ Run one CPU with 1.5v to the RAM modules, and the other at 1.65v
Both CPU's degrade ~ advice given via webchat was inaccurate and that person should be shot... J/ks (no... really)
Only CPU with 1.65v RAM degrades ~ IMC has degraded
Edited by Ishinomori - 6/1/11 at 12:36pm