Originally Posted by dcpmark
Just upgraded the last 2 of my Series 3 units to a Roamio + Mini. Both have lifetime subs on them, and both are upgraded with newer power supplies and 1TB WD drives with 157 hours HD/1367 SD. One is an S3 and the other is a TiVO HD.
What are they worth if I put them on Craigslist or eBay?
The 648 is worth more than the 652 because--
a. It was a lot more expensive new, sort of a Cadillac to the 652's higher end Chevy, so there's a psychological element to it.
b. There are fewer of them being dumped on the market.
(that may be because more 652s were sold than 648s to begin with--you never see anyone advertising an unsubbed 648 new in the box, never used, the way you sometimes do 652s, or it may be that 648 owners are less inclined to give theirs up than 652 owners, or both)
c. The big one to me, because I've successfully moved a crypto chip from one motherboard to another (and in another year or two my nerves should recover from the experience), the 648's crypto chip, which holds the TiVo Service Number, to which lifetime is tied, can be moved to another 648 motherboard if the first mobo goes bad, thus making TiVo think the lifetimed board is still working, and therefore saving the lifetime sub, whereas starting with the 652 and 658 (HD and HD XL), the TSN is encoded someplace inside the CPU package itself, which means you could probably replace the 652 and the lifetime sub cheaper than getting the CPU moved because of the Ball Grid Array mounting, as opposed to the 648's much simpler Surface Mount Device mounting of the crypto chip.