[The Fifth Horseman]

Since I've nearly ran out of space on the HDD's of my home computer (80 + 120 + 250 GB, all on ATA interface), I've decided to buy a new drive to back up my current stuff so I can free some HDD space. That will be concurrent with burning all the transferred items to DVD's (each in duplicate, for paranoia's sake).

Now, I'm not exactly that much up to date on my knowledge regarding HDDs or their pricing, so I'm looking for advice.

For the moment, I know it'll have to be an internal drive with 500 GB size and max price of 450 PLN (aproximately $180).
The drive will NOT be permamently installed into my machine (to extend its longevity and ensure safety of its contents), but rather connected only to back up the data and retrieve it later if neccesary (only if both DVD's fail).
Altough some of you might prefer external USB drives for this kind of thing, I've had some bad prior experience with these and as such am pretty definite on the subject of the HDD being an internal one.

Regarding the drive's interface, I'm not sure whether it should be ATA or SATA.
The three currently installed HDDs and the DVD recorder all use ATA interface leaving no further space for ATA devices unless one of them is disconnected (my motherboard is an ASRock K7-880 with an integrated SATA controller... I think it's not SATA-II, but will check the specs when I'm back home). After I move out the files, I intend to unhook the 120-gigger for use in a different PC, though.
Obviously, since the drive will be used for backup purposes only, the speed of data transfer is not a priority.

I'm completely confused regarding the things like NCQ and perpendicular write, though. Will they be of any use for me or can I just disregard them?

Also, which manufacturer would you recommend? And why?

Thanks.