I have recently overclocked my i5 4670k to 4.3ghz.
It requires no less than 1.17v to be completely stable.
I don't really want to push it past this. The only odd thing is that i can see practically no temperature change at all and makes me wonder if i should push further.
I am able to run stable 4.5ghz at 1.2v but was worried that this may shorten the life of my chip.
My question is, with not much temperature change will the life of my chip be degraded at all, if so will it be noticeable?
I am getting around 52 degrees under full load and 25-30 degrees idle. I am using a h80 corsair water cooler. I understand that these temperatures are ok but am slightly worried to run my chip at higher frequencies as i don't want to damage it, any advice would be appreciated.
That's actually an excellent temperature and speed for that voltage. It seems you may have a golden chip. Frequency won't damage your chip, voltage will, but the degradation caused is insignificant if you are not going for very high voltages.
I would recommend trying to see how far you can go while maintaining reasonable temperatures, and save a profile in your BIOS when you will need it. If you are gaming, you don't really need that much power. Keep it at a good clock speed for daily usage (or stock and all power saving settings on, you choose) and activate that particular profile when you need more processing power.
What sort of degradation would you see at 1.25v? is it the difference of it running for 7 years rather than 8? should i be worried to run it at that voltage if i am seeing perfectly fine temps?
I don't think major degradation will occur at 1.25V voltage. If you start pushing above 1.3V, then it might occur. You will know the silicon is being degraded when from time to time, you will need to increase the voltage to keep the CPU stable at the same frequency.
CPUs can last a very long time if not pushed to extreme levels. You won't have to worry too much about 1.25V.