Last night I began to notice that one of my datastorage drives is becoming quite unstable and smart tests revealed a number of errors. So now I´m looking for a drive to replace it.

I want a drive which is about 1 or 2 TB. My failed Hdd is a Wester Digital and I have 3 other Samsung drives which I quite like. Was thinking about getting a Samsung F3 TB but unfortunately Samsung sold its Hdds to Seagate and they immediately cut the warranty down to 1 year so I´m not too sold on them.

Could someone recommend a quit and reliable hard drive which must´n be that fast because it will only be a data / backup drive? Thanks for your help!

Sounds like you don't trust WD anymore, otherwise I would recommend a WD Green. Long warranty, quite and needs less energy. The green line isn't as fast as the black, but for backup they is really good On the other hand you get for the black line much longer warranty time. There is also a new line called red especially for nas systems (longer warranty, less compatibility problems, etc), but I really can't say anything about it yet.

I still trust WD ;) The failing Hdd is 10 years old so I think it´s about time it´s behaving strangly. I don´t trust Seagate. Will check out the WDs you mentioned. Thanks!

Green drives of any brand are worse than the non-green versions are. I personally don't trust WD anymore, but that's just me.

I'd recommend the OP get a UPS if he doesn't already have one. I found that my drives started lasting a lot longer after I did that. People often times don't realize how much damage dirty power does to data.

Also, I'd recommend the OP get an online backup service like Crashplan as well as making liberal use of QuickPar and DVDisaster as needed on individual files and discs so that he knows what is and isn't corrupted. Also, dvdsig to find data corruption more quickly.

If I was going to buy a new HDD right now, I'd go for a WD Caviar Black. Can't argue with good performance and a five-year warranty. The Green is considerably cheaper per gigabyte (and probably quieter and more economical in terms of power consumption), but it only comes with a two-year warranty which isn't good enough for me as all electronic devices I own have a tendency to break much sooner than I'd like them to. The only exception to this rule was my first mobile phone which worked for six years without a hitch and remains in reserve in case my smartphone takes a shit on me. It probably will.

Maybe I´m stupid but what do you mean with UPS? Power Supply? I use an Enermax Pro 28+. Guess it´s good enough. Will check out the programs you mentioned. Thnaks. Just ckecking out the Caviar Black on amazon. One of the few Hdds with very good customer ratings. Is it really as loud as mentioned by a lot of users?

I must admit I usually just buy the cheapest I can find for a given size, because it seems to me it is mostly a matter of opinion which brand lasts the longest, and you can never tell how people have mistreated the HDDs that have failed on them. Over the years some different HDDs (mostly PATA so far) have failed on me, from many different manufacturers. And then other drives from the same manufacturers have lasted a decade(s), and still going strong. E.g., the old PATA drives I don't use anymore with my old desktop PC, I now use them either as external USB data storage drives, or swap them to my TV recording box (which accepts only PATA drives).

For example I bought two 2 TB 3.5" Seagate HDDs for long-time data storage (two, because I keep two identical backups all the time, so if one of the HDDs fail, I have one backup left). They were the cheapest 2TB drives I could find. I guess I could have bought some much pricier brand too, but then I could have afforded to buy only one. The prices seem to vary wildly.

For my new laptop, last week I also bought a 2.5" Western Digital Scorpio Blue 750GB 5400rpm to the free HDD bay it has. As a default it already had some 2.5" 750GB 7200rpm Seagate as the primary HDD.

Question related to that: does the 5400rpm vs. 7200rpm affect how long the HDD might last? I would think the slower spinning model would last longer and produce less heat, but then you never know, maybe they are always made of cheaper materials to begin with? Anyway, so far I don't care that much if it is 5400rpm, speed is secondary to capacity to me, as long as it works. This is also why I don't even consider SSD drives for now due to their restricted capacity, even if it would have made sense to put a fast SSD as the primary HDD on my laptop, and keep the bigger non-SSD HDD as the secondary data-storage drive.

Never had any problem with the greens, but the difference between the warranty to the black is really disturbing. It seems WD is dropping the blue to make the green to the new basic series. It seems red is the new green then. So, maybe it's really the better to go with a black one.

Thank you all for your help! I went with a WD Caviar Black 1TB. Has very good reviews on various sites and a 5 year warranty. Should also be quite fast.

Nah, more like a backup thingy when the power goes off, but you leave it plugged in all the time. At least thats what they do with the servers were I work.

http://en.wikipedia.org/wiki/Uninterruptible_power_supply ;)

The problem is that every time the drive spins up and spins down it shortens the lifespan of the drive. Green drives do that more frequently to save power than the other models do. Most of the time when I've had a drive go bad for reasons other than bad power it's been because the spindle motor is broken. And you hear that awful whir click sound.

Usually the green drives are the energy efficient drives, so I'm not sure what's going on their if they're relabeling things like that.
It's a back up, but it's also typically a line conditioner as well. Smoothing out the voltage so that you don't have under and over current conditions. I haven't actually seen a standalone power conditioner sold in years. Apart from the ones that cover the whole house.