Does overclocking reduce cpu lifespan?

So, at last i have just overclock my intel E4500 cpu in my intel946gzis motherboard. Not very much, but decent for me. I have done it by bsel mod(bsel 1 to bsel 2) to change fsb from 200 to 266, my E4500 running at 2.93 GHz. And this is my 1st time at overclocking.
I am using heatsink and fan which come with the processor.
Temperature from speedfan--- 43'C@ idle and 74'C @ 10 minitues of orthos small FFT test. Is this ok?

Will this overclocking reduce my cpu life span? I want to last this cpu at least 3 years.

Guys , do you give me some advice about those? I know some of you have lots of experiences in cpu overclocking.

General rule is heat and vcore.

That temp is pretty high. I'd suggest an aftermarket cooler to keep the temps down and for the sake of longevity keep the voltage under 1.5v.

Go read the sticky thread on CPU temps!!!

My voltage is default. CPU Z shows 1.325 and speedfan shows 1.2-1.3.

There are three types of temp in speedfan,
at load it shows CPU : 73-74'C
Core 0 : 67-68'C
Core 1 : 67-68'C
It's summer here so ambient temp around 30'C.

There are three types of temp in speedfan,
at load it shows CPU : 73-74'C
Core 0 : 67-68'C
Core 1 : 67-68'C
Could u guys tell me which is actual CPU temperature?

As long as the voltage and heat is low you'll be fine.

As others have said, that temp is a little high (assuming it is correct). What cooler do you have? How is airflow in your case?