Iv been told i should keep my computer running 24/7 and again i was told to shut it down...The say by running it 24/7 stops the system from expanding when it gets hot then shrinks when it gets cold.. Some say keeping it running will expose you to viruses....id like to know whats best for my computer..
I run mine 24/7, cause I can't stand waiting for my system to boot. As trivial as that sounds, but I am also running Folding@Home and like instant gratification when I want my computer.
The processor shrinking/expanding is quite urband legend and I have never seen any technical info showing 'scientific data' to prove it's validity.
If you're the kind to constantly go to your computer, then away, then back, I suggest leaving it on. If you are a get on and work for 3-4 hours then not touch it again the rest of the day or are on the extreme wing of energy conservation, I'd say turn it off.
You could also do a happy go between and try sleep modes or hybernation after an hour or so (time dependant on how often you access your rig).
What you do is really a personal choice, but you're not going to kill anything by leaving it on OR turning it off.
Oh, and as for viruses, doing stupid things or clicking on things you don't know where they came from, or not having your virus AND malware programs running and updated is the way to get exposed to viruses, not leaving it on and idle... IMO