Date: Fri, 17 Feb 2006 09:29:06 -0800 From: "Ted Mittelstaedt" <tedm@toybox.placo.com> To: "Mark Ovens" <marko@freebsd.org>, <freebsd-questions@freebsd.org> Subject: RE: 80 pin SCSI hard drives. Message-ID: <LOBBIFDAGNMAMLGJJCKNEEGLFDAA.tedm@toybox.placo.com> In-Reply-To: <43F5EBE5.9000904@freebsd.org>
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Mark, The problem you have with the 80-pin to 68-pin adapters is this. A lot of the el-cheapo adapters do not terminate the unconnected data lines, that is when you get instability. The better quality adapters do terminate them and don't have instability problems. Ted >-----Original Message----- >From: owner-freebsd-questions@freebsd.org >[mailto:owner-freebsd-questions@freebsd.org]On Behalf Of Mark Ovens >Sent: Friday, February 17, 2006 7:30 AM >To: freebsd-questions@freebsd.org >Subject: Re: 80 pin SCSI hard drives. > > >Alfredo Finelli wrote: >> I have 80 pin SCSI discs mounted in hot-swappable trays on a SCSI >> backplane which takes care also of powering them up and of SCSI >> termination. This is one way of using them. >> >> I also have the same drives in a different system connected >to normal SCSI >> LVD cable using small adaptors which have an 80 pin receptacle on one >> side and a 68 pin SCSI connector plus 4 pin molex power >connector on the >> other, as well as jumpers to define SCSI id. In this second case you >> have to provide the required termination of the SCSI bus >(e.g. using the >> right terminated SCSI cable). >> > >So you can confirm that using these adaptors works OK? When I bought my >SCSI drive (off eBay) there were more SCA drives for sale than 68-pin >but doing some research about 80->68 pin adaptors I found a lot of >people saying not to use them, including Adaptec: > >This from Adaptec's ASK knowledgebase http://tinyurl.com/b3ofa > >"Although there are adapters on the market converting 80 pin to 68 pin >they are not supported by Adaptec or the hard drive >manufacturers. These >convertors can cause loss of signal integrity that may result in >connectivity issues and data loss." > >This put me off getting a SCA drive. Now I'm looking for a >another drive >and SCA ones seem to be cheaper on eBay. > >Regards, > >Mark >_______________________________________________ >freebsd-questions@freebsd.org mailing list >http://lists.freebsd.org/mailman/listinfo/freebsd-questions >To unsubscribe, send any mail to >"freebsd-questions-unsubscribe@freebsd.org" > >-- >No virus found in this incoming message. >Checked by AVG Free Edition. >Version: 7.1.375 / Virus Database: 267.15.10/263 - Release >Date: 2/16/2006 >
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