I read somewhere that it is better to keep the cpu running on, for “warm-up” purposes. Is it true? Or should the cpu be kept shut down for a specific length of time?
Better for what? Unless you have a very specific reason to be concerned about it (heat/power comsumption in a server farm), I wouldn’t be. You can play around with something like CpuIdle, http://www.cpuidle.de/, or just power off the PC when it’s not being used or use sleep/hibernate mode. Of all the computer components that I’ve had fail, the cpu was never one of them.
From my experience of repairing PCs, I’ve experienced the following hardware failure, starting with the most common failure: HDDs (few per month), DVD burners, Fans, power supplies, motherboards and RAM modules.
However, I haven’t encountered a single confirmed CPU failure over the entire period I’ve worked with PCs. Even with all the times I’ve seen CPUs with heatsinks clogged with dust, fan failure, etc. it was just a matter of dusting off the heatsink or replacing the CPU fan and it worked fine after that.
My recommendation would be to periodically dust out your PC, as an overheated PC is one culprit between hardware from my experience. Use a can air duster. I know they’re pricey, but it’s cheaper than replacing parts that overheated. The worst case scenario I’ve experienced was when someone asked me to look at their PC that kept randomly rebooting and showing BSODs. After spending a while trying to find the culprit between the BSODs, it turned out to be a combination of a badly dust clogged CPU heatsink (Speedfan showed a CPU temperature of 107Â°C ), hard disk failure (lots of bad sectors), one bad RAM module and a failed case exhaust fan.