-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 At some point hitherto, Michael O'Donnell hath spake thusly: > because I don't see how owning a new (versus > used) RAID controller saves you if it fails. > If you can get a replacement controller under > warranty why can't you get a replacement > controller by other means? Anybody here who
The point is, whether or not it's a good value to buy a used part vs. a new part depends on many variables, including the specific hardware, the user's need for that hardware, the vendor and their warranty policy, the relative costs, and the purchaser's aversity to risk. So it's not a clear-cut argument, either way. I think it's largely a risk management argument. If you decide you want to buy cheap, used RAID cards, and it fails, you need to buy another cheap, used one. How many failures does it take for it to become more expensive than buying a new card, which is replaced for free under manufacturer's warranty? Whether or not the used card is more likely to fail than a new unit of the same item is a function of things you probably can't know, mainly how the hardware was treated prior to it arriving on your doorstep. Therefore, it becomes difficult to assess the risk involved in buying used cards (or, as a measure of risk, how much it will cost over some period of time to buy used RAID cards). If you go with used cards, and they typically cost you $100/card, and the MTBF is 1000 hours, then every 10,000 hours you're looking at $1000 in used cards. This ignores the fact that the used card will have some of those hours already used up, in all likelihood. [Note, I'm not saying that is a reasonable figure, I'm only picking the number out of a hat to use as an example.] OTOH, if a new part has the same MTBF (1000 hrs) but has a lifetime manufacturer warranty, and it costs you $400, then every 10,000 hrs you're looking at $0 plus your original $400. That makes it a better deal. In case it's not clear what I mean, the costs for used and new cards in my example are: used: 100x new: 0x + 400 where x is the number of failures. It's also worth noting that some hardware which has a lifetime warranty may have a *transferrable* warranty, so if you buy it used, you don't lose out if it dies. Other hardware may not have a transferrable warranty. You may or may not need to provide proof that you're eligible for said warranty, which you may or may not be able to do. If the $400 for a new card is a lot of money to you (or the organization you're buying for), and you *need* the part in question for some important use (i.e. you're not just buying it to play around with SCSI hardware), then depending on the terms of the warranty, it may well be worth it to buy the new part, even though it costs more up front, because it may be cheaper in the long haul. And, some people and/or organizations may prefer to go that route without considering the used route, so as not to have to take a gamble on how long the hardware will last, or more importantly, how much it will cost them to keep replacing it when it dies. This argument ignores several factors, including: the cost of labor for replacing the hardware, if your staff does it, vs. having a warranty service technician do it for you; the cost of down-time when the hardware fails; the cost of shipping the part (e.g. when purchasing a used one, or when shipping one to be repaired or replaced); whether or not a used card is or isn't more likely to fail than a new card, on average. The reasons for ignoring those factors are that in many cases, they can be assumed to be the same in both cases, and in many cases, they are too variable to consider directly. For example, your vendor may pay for shipping the defective part back to them. Many vendors DON'T do that. In the latter case, you could assume the cost for shipping would be the same (per replacement), so it would cancel out. In the former case, you'd clearly need to factor in the cost of shipping the used part, since there's no shipping on the warranty part. Ultimately, you'd need to do a more careful analysis after having all the facts. - -- Derek Martin [EMAIL PROTECTED] - --------------------------------------------- I prefer mail encrypted with PGP/GPG! GnuPG Key ID: 0x81CFE75D Retrieve my public key at http://pgp.mit.edu Learn more about it at http://www.gnupg.org -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE8o2n6djdlQoHP510RAi2MAJ4ytSkPaY5bGr25pP6PgIB6H58H9wCfS8iz lRTGp78lOffVHoCS+zaj2u8= =zWnW -----END PGP SIGNATURE----- ***************************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the text 'unsubscribe gnhlug' in the message body. *****************************************************************
