Last week the ST31000528AS was on special offer everywhere in high volumes but now... good luck finding one from a mainstream UK vendor; it's possible the few that are still out there are rag-tag customer returns. The drive, apparently discontinued on Friday 25th March, which has been through twelve revisions, appears to be no more ("1TB Seagate ST31000528AS NOW EOL - Replacement is LN37556" - I drew a blank on the latter but) and is apparently replaced by the SATA 6 compatible version, which itself has been reduced in price. The drive's claim to fame according to Tom's Hardware stats and others is it ran cooler than the immediate competition, used less power and was, when working to spec, quieter too, unless you went for a slower running 'green' drive. Ideal for an iMac. Why am I lamenting it's passing, here? One possible workaround for a very noisy Seagate was to buy an identical drive. Buying an identical drive wouldn't work in and of itself because Apple flash those Seagate drives with their own firmware to deliver the correct temperature information to the 2010 iMac's mainboard; without an Apple-firmware-flashed hard drive circuit board the fans in the 2010 iMac gradually runs up to full speed - even with the correct manufacturer-specific temperature cable in place that unaware Mac hard drive vendors said would work. A possible workaround, though, I think, if you confirm the hard drive revisions are otherwise identical, would be to remove the logic board from the Appled-Seagate and put it on a replacement ST31000528AS; if the noise was purely a mechanical fault that's one workaround (an earlier revision Seagate had a firmware update to quieten the drive but Apple-d drives could not be flashed with this). I haven't tried it, at work I usually to fit Samsung and Western Digital drives to PCs, but I have had friends give me their old non working Maxtor drives, for instance, to try and rescue data. If the mechanics are still sound, I order an identical revision of that drive and switch the circuit boards around. Worth a try? Absolutely not. Obviously return your iMac if still under warranty with a print out of the reams and reams of forum posts on this contentious hard drive and the faulty ones that make your iMac sound like a popcorn maker throwing small rubber balls around. My illness is that I am a tech, I don't like others hurriedly poking around inside my computers; I would make an exception with the iMac but that I don't have a car and there is no Apple store in my city. Still, my patronizing two cents is I wouldn't advise anyone to open their iMac. Anything expensive that is still in warranty and with ribbon cables inside it is best left alone. Also, even assuming the replacement ST31000528AS you order is the same revision as the one in your iMac, even assuming it works, if you send your iMac in for a service the tech is going to be greeted with a hard drive that doesn't have the Apple sticker on it. I can't speak for the iMac but the few other Macs I have worked on, the hard drives had non-cleanly removable Apple stickers on them. I have noticed that there are a lot of 1tb Seagate external drives on special offer at the moment. Quite likely it contains the famous ST31000528AS. Perhaps someone can confirm this. The more recent Seagate FreeAgent GoFlex 1 TB Desktop might be worth a gamble. You could still end up with a noisy sample but, all being well, and you're a crazed gambling DIY sort, you would have a spare USB 2 hard drive enclosure that can also take a hot swappable USB 3 or Firewire 800 conversion kit. The non April Fools joke, as always with dear and desirable iMacs, is that if you wanted a computer that you could user service and upgrade, you should have saved a little bit/lottle bit longer and bought a Mac Pro.