should i replace thermal paste?

[sancco]

i have an i7 4770 (non-k) that is peaking at 65°C. it used to peak at 57°C a year ago. should i be replacing the thermal paste, or can i leave it a bit longer till i bother?

also, what temperatures start to diminish cpu lifespan? i've been reading hugely varied figures (70°C-100°C). thanks

 

[HEXiT]

its unlikely the paste is the issue if its only been on for a year. typically you wont need to replace the paste on a stock heatsync for the lifetime(5 years) of the cpu. if however you used a 3rd party paste then you would still have 2-3 years before you need to replace it.

if however you removed the heatsync and just put it back without applying new paste then its possible you have an air pocket.
if so you can still fix it. just by releasing the clamps and pressing firmly on the cooler. then gently rotate it left and right till you feel the resistance go from spongy to firm. then lock it down and see if the temps fall.

still not the issue? then look at your cooler and fan.
maybe they are clogged with dust. clean your fins and blades as well as any filters your case has.

as for the temps get a copy of real temp and run it. see what the tjmax is and make sure your under 75% of that value for your max temp. this will ensure you get the best possible lifespan from your cpu.