The quick test way is if you have a desktop with a SATA "dock" to slip the drive in question into to
your desktop and use a program like Piriform's "speccy" to read the S.M.A.R.T. data on the drive.
(SMART cannot usually be read on drives connected through USB or through PCI controllers)
Reallocated sector count and uncorrectable sector count are the first two line items to look at...
frankly if I see anything other than a zero in either of those columns I retire the drive from "first line" service. Basically that means they will never again get used to hold an operating system.
this however can only "indicate" (or not) if you have a problem, but it can't prove it one way or the other.
On a notebook drive 3-years is stretching the rubber-band a bit too far for any reasonable
degree of confidence and on a notebook drive (unless you have a cloned backup of the drive) you lose everything WHEN (not "if") the drive fails.... Just how confident are you that your drive is good?
It's "cheap" to replace the drive when YOU decide to do it, even if you follow my recommendation
to buy TWO new drives it's cheaper than what It's going to be for labor, let alone the cost of the
drives and OS if you need to do it after a failure
My personal Laptop is a Dell1525 that was produced in Feb of '2008, I "retired"
(I still use it as a USB drive) the original HDD in July of '09 when it was 18months old.
For my notebook I have two identical 320gb HDD's that are clones of each other.
If one fails I'd only be down for as long as it'd take me to swap drives and restart and since my
backup drive is already in a drive caddy... (2 screws and I never have a #1 phillips further out of
reach than my coffee cup)
Professionally I don't trust ANY single hard drive, but then again I don't have anything that I
trust to only ONE HDD.
Notebooks by nature are "single drive" entities, and thus in a way are "designed to fail"
While I'll lament the reality, that reality keeps me fed, because no matter
how I warn people, people I know and see in person daily, they just don't listen...
Like I have been oft quoted... "Lack of planning on your part does not constitute, suggest
or imply an emergency on my part"
a Hard drive failure when that HDD is the host for an operating system AND there is no clone for the HDD in question? the only appropriate word is "disaster"
Can you prove it's the HDD? not easily
My usual tack is that it cannot be readily proven that it isn't the HDD
So in essence I've gotta say "Guilty until proven innocent"
IF it is later proven to not be the HDD you can either use the HDD as a "Back-up" or you can get a USB enclosure to put it in to use as a portable data drive.