I upgraded my Sky+ box with this 500GB HDD, and everything works totally fine, not noisey at all. Would recommend this drive to upgrade your Sky+ box, which is very easy to do. Just replace the HDD and do a full system reset and wait about an hour.
I had one of the original 40GB boxes which was tiny and soon filled up, not ideal for family use, 20 hours storage soon fills up.
Now I have more than 10 times the previous limit, approx 250 hours (!) Makes a big difference and no longer have any issues recording and time-shifting for the whole families needs.
This upgrade has brought a new lease of life into an old box and is even better than the new PVR3 boxes which have 160GB, but actually only have 80GB of personal use as the other 80GB is used for Sky Anytime. A nice feature but pity owners don't have the option to decide what they would prefer, Sky Anytime versus more storage space for own use.
If you have an old Sky+ box, get frustrated by the lack of space to record, then you won't regret this drive to upgrade. Just do it and enjoy the freedom to record what you want and watch when you want, as it was intended, not how much space do I have left!