Hi,
Here’s my 2 cents worth based on 10 years experience working in IT… hardware generally lasts longer with continuously connected to power, than connected/disconnected all the time. However, in the real world the machine is likely to become obsolete well before this makes any difference.
Environmental factors are really what causes the most damage, #2 being heat, and #1 being power. If you’re using your laptop in hot conditions, look into one of those giant heat-sink laptop stands; heat is evil.
I’ve lost count of number of machines I’ve looked at over the years that have had components fried by power fluctuations. With laptops this is more of an issue, since unlike desktop pc’s you [often] can’t replace individual components. Basic surge protectors are better nothing, but don’t provide much protection and are a waste of money in my opinion; not all power damage is caused by surges, and most surge protectors only block large-ish surges, and don’t do anything for ripples or brown-outs (the opposite of a surge).
I do have inline surge protector for when i’m traveling, but it was mainly to protect modem port from being fried than the ac side of things (it’s a AC & RJ-11 combo unit); especially since the modem is soldiered directly onto the motherboard
What you want is something that guarantees a clean power supply. I’ve seen a lot of customers waste money buying UPS’s when they would have been better off with a power regulator instead. UPS’s are important for server environments, were the box must stay up no matter what, however UPS’s don’t provide much [if any] in the way of power regulation, they just provide power when the mains are out; you’re paying for a large stack of lead acid batteries.
A good power regulator provides a clean AC sine wave at exactly 240v/110v. Regardless of the voltage at the outlet, the power supply to your machine stays rock solid at 110v (or 240v depending on your region). They store power in large capacitors and use that to create the clean feed; generally speaking anyway.
In high-end data-centers you’ll often see, power regulators and UPS’s connected in series (or a product especially designed to do both, often wired directly into the mains of the site).
For more information see:
APC Line-R (the 600VA unit is suitable for most applications):
http://www.apcc.com/products/family/index.cfm?id=67
I’ve been using APC Line-R units for 15 years, and have *never* had a hardware failure… (though in the case of hard disks, i think i’ve just been lucky, sometimes they just go… but i’m sure clean power helped)
There are other brands out there, but it’s a bit like insurance—-is it really something you want to scimp on and hope you’ve got enough cover when the time comes? Especially considering the APC unit retails for under $50? (search for “apc line-r 600va” on amazon.com). Btw, no i don’t work for APC, lol, i’m just a happy long-time customer of theirs (same goes for clients i’ve recommended their products to over the years ) I’d say the same about Wacom too; just got a silver graphire3 to use with my TR3 when i’m travelling
Hope that helps,
Matt.