Power management and laptop life

Ok so i ahve 2 diff laptops (well one is my moms) that are used in different ways and I am trying to find out whether I should be powering off/hibernatin/stand by to best prolong the life. Another thing is i have been told it is best to let the power run down and recharge too (i.e. its not good to leave them plugged in 24/7?).

So here we go, PC 1. Its a desktop replacement. I am in nursing school currently and so my schedule is somehwat strange. For the most part this computer gets used a lot. When I am home it probably never goes more then an hour without being used and thats probably not all that often. So in between uses when I am at home I imagine standby is right if I am not keeping apps open and hibernate is right if I intend to keep apps open? Now of course I ahve to go to class and go to the hospital so there are times when I am gone for 4-8 hr stretches. Is it best to shutdown in these cases? I've just heard that complete shutdowns put a strain on your motherboard and that its best to avoid them. And finally, should I be unpluggin and letting the power run down?

PC 2, this computer is probably on no more then an hour a day, it too is also a desktop replacement. So the thing that concerns me with this one is the constant shutting down and turning back on from a complete shutdown and also that my mom keeps it plugged in constantly. So I assume I should instruct her to let the power run down maybe once a week? Should I instruct her not to shutdown every time?

I know I mentioned that both of these are desktop replacements, not sure if this could've gone unsaid or not but as such I'm generally not concerned with them ebing juiced to take out of the home. in general there will 99% of the time be an outlet to plug into.

[dcc]

Nichol Cadmium batteries are the one that you would want to allow to run down before you recharged them.

Laptops use Lithium-ion batteries, here's part of an article that explains the best recharging practices.

A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

The rest of the article can be found here.

You should not run the computer continuously off AC, the battery needs to be used to keep it healthy. Your owners manual should have instructions regarding this.

As for power management, if you are concerned about power conservation then I would suggest hibernation.

Not really worried about the power consumption per se. More so I am wondering if its better for the life of the pc itself to not to a complete shutdown? I thought I had read that you should avoid shutting down the pc completely as it hurts the pc's motherboard to boot up cold???? Not sure if its tru just heard it somewhere along the way.

So I guess I am wondering if I should shut down and leave unplugged, or should I hibernate/stand by and leave plugged in? Or am i making this out to be more the it should?

[dcc]

Cold boot aren't hard on it, the only real issue there is that thermal cycles help break down component. But this is happening so slowly that it's really a non issue for most. I know people who keep their desktop computers on all the time, they enable the hibernation and leave it. There are differences between standby and hibernation, you can google "standby vs hibernation" for comparisons. As I said, I prefer hibernation.

As I suggested previously alternate you use of the two power sources to keep you battery healthy.