Larger HD's for 630
My experimentation shows that only " 1Terrabyte and smaller drives work " in 630 receivers.
These are full size drives in external drive dock powered externally separate from receiver
These drives have worked for me
Seagate 250G, and Pipeline 1terrabyte,
Western Digital WD10EADS Green 1terrabyte, WD1001FAS Black 1terrabyte
These drives have not worked
Samsung HD204UI 2terrabyte
Western Digital WD15EADS Green 1.5terrabyte
Seagate ST33000651AS 3terrabyte (drive actually partially formated to 593Gigs which is about 25% of what it should be)
If you try different drives, have one you know that works to put in after one that doesn't work because receiver still looks to format a drive after one fails and should you put in a drive you have recordings on it will format it wiping your saved recordings. Did that a couple of times till I caught on.
All the above drives that did not work in 630 receiver worked in 530 receiver, except for the Seagate 3T drive, again only a portion of it formatted.