One of drives failed (SMART) today; right before I have to take a out of town trip. I have not had a HDD failure in 4 years. It is still under Seagate warranty. Will process RMA next week.

you think it has anything to do with their refurbished nature?

I doubted, my previous refurbished (replacement) drives never have problem over 5 years. I did come across my mind for a few seconds.

That's why USB HDD comes in handy for backup.

RMA returned on Nov 21, replacement arrived today.

a good 2 weeks still, I have 320gb Seagate HDD which failed on me, will have to send in back for RMA too

In my case, they did not have the same drive in stock. Otherwise, there is a charge for $19 and they ship you a replacement immediately without receiving the defective drive first. If the "defective" drive is not sent or received by Seagate within 30 days, a charge will be made to your credit card. It seems a normal practice for WD also.

How old was it, and what happened to it? I have quite a few of those drives...

about 1 year old, when copying data to the drive, the copy operation would hang and the drive would disappear from device manager.

Tried format 010101 with Seagate tools (what we call low level format) and scanned the disk, no errors were found on the platters but SMART keeps giving errors on the quick test, stating that operating temp went over 70°C, but the HDD has never reached 40+°C I'm sure of it, dedicated cooling and all for each HDD in my previous file server case.

Hard-drive is a relationship; everyone needs it. It does not matter how well you care for it, no one knows when she/it walks out on you. When it does, you always have a feeling of betrayal. The first time is always the worst; she/it takes all your secret not knowing if she would fall into the wrong hands. You would learn how to protect your secret as time goes on in your next "relationship". When you hair turns grey, relationship has an entirely different meaning; you tend to not rely on it entirely and always have a backup.

Yes, but I would like to know what to look for, can at least hypothesize since I have the same drives some will most likely develop the same issues before "walking out" on me.

Unfortunately I had a Western Digital drive do that exact thing to me, minus the SMART warnings.

Speedfan to check S.M.A.R.T status; unfortunately there is not much of a warning at times. In three occasions, the drives were working fine the day before, on the following day during boot up a BIOS message prompts "your HDD is leaving you, back up the disk". (not the exact words mind you ".

At one time, the BIOS won't recognize the HDD at all. When she decides to leave you she doesn't give you the normal two weeks notice. Sometimes she will "b***h" for awhile, a signal that she has had enough of you. 1 WD, 2 IBM (hitachi now) and 1 Seagate, surprisingly I have 4 or 5 4.3 GB still in good condition after +5 years of use.

As long as she doesn't win the inevitable custody battle over all my stuff, I'll be happy.

Hence, backup "plan". including hiding some of your assets such as offshore banks and property investment etc.

if you get bad sectors and really want the data back, you can try the freezer trick

today one seagate comes to me, it is better than WD or hitachi whose I had in my computer, it is very quiet and it's faster than other HDD, but if you buying new seagate took at last number who needs to be on 250gb
310AS (disc with 8mb cache)
4100AS (disc with 16mb cache)
On 320gb and 400gb:
620AS
and on 750gb 640AS