What's safe for a long term overclock?

[Deus Gladiorum]

Almost 6 or 7 months ago by now, I ended up overclocking my FX-6300 to 4.5 GHz. It's really stable according to nearly 24 hours in Prime95 and completing a bunch of IntelBurnTests without fail, but to get to 4.5 I raised my voltage by +0.125 according to my motherboard, iirc (it's been a while and I'm not near my computer to check if that's accurate). From what I remember in CPU-Z, the actual voltage would at most be 1.428 V though it fluctuates below that.

For a long-term overclock, is that good? More and more I've been reading about overclocking haswell lately and I know it's a different chip entirely but people are constantly talking about making sure it's an overclock ready for long term use and so they only raise Haswell to the 1.25 V range or something. So is my overclock also fine at such a high voltage?

 

[Verindae]

Apparently there's no official stated safe voltage range for FX chips from what I've seen, but the consensus seems to be 1.55v max. Anythin below that is safe long term because it's within design parameters, or so it would seem.

Edit: Intel chips have a lower voltage range than AMD ones, if you want a closer comparison look to AMD's other processors.