Hard drive question?!?

They are a mechanical device, and will wear just like any mechanical device. Sometimes you'll see a drive start to slow as the drive motor starts to fail, sometimes the drive will just die without any warning. How does it affect gaming? It really doesn't until it fails.

Yes, they do get worn out. The motors spinning those disk anywhere from 5400RPM to 15000RPM can die. The heads can crash into the disks and damage them. Substrate on the disks can become damaged and bad sectors can result. I generally replace them at or around the time the warranty ends..YMMV.

It can cause boot failures BSODs (assuming a Window$ gaming rig) random hard locks, random crashes, failures to load games, or maps in a game (or crashes in a game when attempting access something on a bad sector). It really depends on the damage to the disk.

You can use the open source smartmontools to view the S.M.A.R.T. information on your harddrive here http/www.smartmontools.org/.

Seeing things like:

187 Reported_Uncorrect 0x0032 100 001 000 Old_age Always - 4294495412
188 Command_Timeout 0x0032 100 001 000 Old_age Always - 4295033313

indicate a serious drive problem, depending on the drive. You'll need to dig a little from the manufacturer to figure out when numbers are out of norm.

Other things will be a series of errors like:
Error 2 occurred at disk power-on lifetime: 3648 hours (152 days + 0 hours)
When the command that caused the error occurred, the device was active or idle.

After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
84 51 00 40 bd d9 08 Error: ICRC, ABRT at LBA = 0x08d9bd40 = 148487488

Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
61 00 40 40 c6 d9 40 00 00:27:44.157 WRITE FPDMA QUEUED
61 00 38 40 c5 d9 40 00 00:27:44.155 WRITE FPDMA QUEUED
61 00 48 40 c4 d9 40 00 00:27:44.154 WRITE FPDMA QUEUED
61 00 18 40 c3 d9 40 00 00:27:44.153 WRITE FPDMA QUEUED
61 00 30 40 c2 d9 40 00 00:27:44.153 WRITE FPDMA QUEUED

Although these errors can be caused by temporary things (sata controller drivers for instance running into a "bug")and also faulty power supplies. In fact, if your drive is within the warranty period and failing, outside of getting a lemon, you may have a faulty power supply or faulty power cable to the hard drive. Nothing ruins an HDD, outside of shock, faster than bad power (or a manufacturer that has gate in its name's consumer division).

Mechanical hard drives are an imperfect technology. I guess no technology is perfect, but mechanical drives are especially notable. They can (and indeed will) wear out. When a drive will fail is almost purely based on chance. Sometimes they'll last a really long time, other times drives will fail within a year. It's a risk you have to take, I'm afraid.

As far as gaming purposes, the main side effect of a failing drive you'll see is longer load times. Other than that, I can't really say much. But in other aspects, your computer will generally slow down, programs will take longer to start up, and in some extreme cases your computer might stop responding altogether (if it tries to access bad sectors on the drive). I have had this happen - I reinstalled Windows several times on a relative's laptop because it kept locking up (completely), and it was weeks before it finally dawned on me to run a SMART test on the hard drive. Sure enough, it was failing.

There's no way to tell indefinitely. I don't mean to sound so bleak, but really all you can do is hope for the best. Like I said, some drives will fail within a year, and some drives will last a quite a long time. For example, last year I had an IDE drive from 2001 that was still bootable. However, as I explained with my relative's laptop, sometimes they fail quickly - in that particular case it was a 320GB SATA drive from early 2013.