I am ordering a new PC and it says it will OC to a maximum of 4.6GHz, I use my PC a lot and it is on most days nearly all day everyday, the PC will be watercooled, will OC effect the longevity of the CPU or have any adverse effects?
Typically a CPU will have an expected life of about 15 years. OC may take a few years off that, but you are likely to be upgrading the CPU long before it wears out. However, like any electrical good some last longer or shorter than others - for example I've known TV's to last for 20+ years, but also for them to fail within 6 months.
Mainly what determines the expected life is how hot they get - typically OCing will increase the temperature, but with sufficient cooling you can offset that to avoid reducing the useful life. The only adverse affect is likely to be if you push the OC too hard then it can make your system unstable - but you should notice this pretty quickly as it will cause the system to crash. PCS's OC service should avoid pushing the processor too hard.
