Why is my SCSI hard drive still running at 40 MB/sec?

I have an Adaptec 29160 SCSI card, one U320 internal hard drive running at
160 MB/sec. For years another hard drive in an external SCSI enclosure ran
at 40MB/sec because although the drive is U320, the external cable
connecting SCSI card and SCSI enclosure is U160 and the external terminator
to the enclosure is U320, the SCSI enclosure internal cable is the old UW/SE
type. (I inherited the SCSI enclosure from the old 2940UW days. I can see
160 MB/sec and 40 MB/sec associated with the two drives when the computer
boots up.)

Recently, I bought an U320 internal cable to update the SCSI enclosure. I
expect the drive in the external enclosure to run at 160 MB/sec now. But I
am surprised to see it is still running at 40 MB/sec. What could go wrong?
All my products besides the SCSI enclosure are either U320 or U160.

Thanks for any suggestion or guess.

Ar Q wrote in news:QvednYOSmv1zPY_VnZ2dnUVZWhednZ2d@earthlink.co m
> I have an Adaptec 29160 SCSI card, one U320 internal hard drive running at
> 160 MB/sec. For years another hard drive in an external SCSI enclosure ran
> at 40MB/sec because although the drive is U320, the external cable
> connecting SCSI card and SCSI enclosure is U160 and the external terminator
> to the enclosure is U320,

> the SCSI enclosure internal cable is the old UW/SE type.

There is no such UW/SE internal cable.

> (I inherited the SCSI enclosure from the old 2940UW days. I can see
> 160 MB/sec and 40 MB/sec associated with the two drives when the computer
> boots up.)
>
> Recently, I bought an U320 internal cable to update the SCSI enclosure. I
> expect the drive in the external enclosure to run at 160 MB/sec now. But I
> am surprised to see it is still running at 40 MB/sec.

Because the cable wasn't the problem.
If it had been your internal drive would have also run at
40MB/s since it is on the same segment as the external one.

> What could go wrong?

Most likely the drive was set to run at 40MB/s max in the bios setup.
Either that or Domain Validation throttles the drive back to 40MB/s.

> All my products besides the SCSI enclosure are either U320 or U160.
>
> Thanks for any suggestion or guess.

The enclosure has either an internal terminator or plug-in terminator.
Is it labelled SE or LVD (you have to look up the symbols)?

"Ar Q" <ArthurQ283@hottmail.com> wrote in message
news:QvednYOSmv1zPY_VnZ2dnUVZWhednZ2d@earthlink.co m...
>I have an Adaptec 29160 SCSI card, one U320 internal hard drive running at
> 160 MB/sec. For years another hard drive in an external SCSI enclosure ran
> at 40MB/sec because although the drive is U320, the external cable
> connecting SCSI card and SCSI enclosure is U160 and the external terminator
> to the enclosure is U320, the SCSI enclosure internal cable is the old UW/SE
> type. (I inherited the SCSI enclosure from the old 2940UW days. I can see
> 160 MB/sec and 40 MB/sec associated with the two drives when the computer
> boots up.)
>
> Recently, I bought an U320 internal cable to update the SCSI enclosure. I
> expect the drive in the external enclosure to run at 160 MB/sec now. But I
> am surprised to see it is still running at 40 MB/sec. What could go wrong?
> All my products besides the SCSI enclosure are either U320 or U160.
>

"Eric Gisin" <gisin@uniserve.com> wrote in message
news:JMWdne-GPaDoFY7VnZ2dnUVZ_tSknZ2d@uniservecommunications.. .
> The enclosure has either an internal terminator or plug-in terminator.
> Is it labelled SE or LVD (you have to look up the symbols)?
>

The plug-in terminator is U320. If the led is red it runs at SE mode. If the
led is green, it runs at LVD mode.

Since it is green, it runs at LVD mode.

"Folkert Rienstra" <see_reply-to@myweb.nl> wrote in message
news:fuvud3$gkv$1@textnews.wanadoo.nl...
> Ar Q wrote in news:QvednYOSmv1zPY_VnZ2dnUVZWhednZ2d@earthlink.co m
> > I have an Adaptec 29160 SCSI card, one U320 internal hard drive running
at
> > 160 MB/sec. For years another hard drive in an external SCSI enclosure
ran
> > at 40MB/sec because although the drive is U320, the external cable
> > connecting SCSI card and SCSI enclosure is U160 and the external
terminator
> > to the enclosure is U320,
>
> > the SCSI enclosure internal cable is the old UW/SE type.
>
> There is no such UW/SE internal cable.
>

I should say 68 bit wide single end SCSI internal cable.


> >
> > Recently, I bought an U320 internal cable to update the SCSI enclosure.
I
> > expect the drive in the external enclosure to run at 160 MB/sec now. But
I
> > am surprised to see it is still running at 40 MB/sec.
>
> Because the cable wasn't the problem.
> If it had been your internal drive would have also run at
> 40MB/s since it is on the same segment as the external one.
>
> > What could go wrong?
>
> Most likely the drive was set to run at 40MB/s max in the bios setup.
> Either that or Domain Validation throttles the drive back to 40MB/s.
>

I have checked the BIOS, the maximum is set to 160MB/s for every device.

I am not sure what the Domain Validation is. Can you explain in detail?
Thanks.

Ar Q wrote in news:Y-mdnTNTto2JCI7VnZ2dnUVZ_gmdnZ2d@earthlink.com
> "Eric Gisin" <gisin@uniserve.com> wrote in message news:JMWdne-GPaDoFY7VnZ2dnUVZ_tSknZ2d@uniservecommunications.. .
> > The enclosure has either an internal terminator or plug-in terminator.
> > Is it labelled SE or LVD (you have to look up the symbols)?
> >
>
> The plug-in terminator is U320. If the led is red it runs at SE mode. If the
> led is green, it runs at LVD mode.
>
> Since it is green, it runs at LVD mode.

As it did before the internal cable change.

Eric Gisin wrote in news:JMWdne-GPaDoFY7VnZ2dnUVZ_tSknZ2d@uniservecommunications
> The enclosure has either an internal terminator or plug-in terminator.
> Is it labelled SE or LVD (you have to look up the symbols)?

It's obviously not SE as the internal drive is on the same segment and not affected by it.

>
> "Ar Q" <ArthurQ283@hottmail.com> wrote in message news:QvednYOSmv1zPY_VnZ2dnUVZWhednZ2d@earthlink.co m...
> > I have an Adaptec 29160 SCSI card, one U320 internal hard drive running at
> > 160 MB/sec. For years another hard drive in an external SCSI enclosure ran
> > at 40MB/sec because although the drive is U320, the external cable
> > connecting SCSI card and SCSI enclosure is U160 and the external terminator
> > to the enclosure is U320, the SCSI enclosure internal cable is the old UW/SE
> > type. (I inherited the SCSI enclosure from the old 2940UW days. I can see
> > 160 MB/sec and 40 MB/sec associated with the two drives when the computer
> > boots up.)
> >
> > Recently, I bought an U320 internal cable to update the SCSI enclosure. I
> > expect the drive in the external enclosure to run at 160 MB/sec now. But I
> > am surprised to see it is still running at 40 MB/sec. What could go wrong?
> > All my products besides the SCSI enclosure are either U320 or U160.

Ar Q wrote in news:MdOdnRSGdfG1C47VnZ2dnUVZ_gWdnZ2d@earthlink.co m
> "Folkert Rienstra" <see_reply-to@myweb.nl> wrote in message news:fuvud3$gkv$1@textnews.wanadoo.nl...
> > Ar Q wrote in news:QvednYOSmv1zPY_VnZ2dnUVZWhednZ2d@earthlink.co m
> > > I have an Adaptec 29160 SCSI card, one U320 internal hard drive running at
> > > 160 MB/sec. For years another hard drive in an external SCSI enclosure ran
> > > at 40MB/sec because although the drive is U320, the external cable
> > > connecting SCSI card and SCSI enclosure is U160 and the external
> > > terminator to the enclosure is U320,
> >
> > > the SCSI enclosure internal cable is the old UW/SE type.
> >
> > There is no such UW/SE internal cable.

> I should say 68 bit wide single end SCSI internal cable.

To tell them apart from the 50 bit wide single ended cable.
Right, good observation.

What part of "There is no such UW/SE internal cable" did you not
understand exactly?

>
> > >
> > > Recently, I bought an U320 internal cable to update the SCSI enclosure. I
> > > expect the drive in the external enclosure to run at 160 MB/sec now. But I
> > > am surprised to see it is still running at 40 MB/sec.
> >
> > Because the cable wasn't the problem.
> > If it had been, your internal drive would have also run at
> > 40MB/s since it is on the same segment as the external one.
> >
> > > What could go wrong?
> >
> > Most likely the drive was set to run at 40MB/s max in the bios setup.
> > Either that or Domain Validation throttles the drive back to 40MB/s.
> >
>
> I have checked the BIOS, the maximum is set to 160MB/s for every device.

> I am not sure what the Domain Validation is.

Adaptec's site and Google's both offline again and on top of that you
also misplaced the card's manual. Jeez, you sure don't have much luck.

> Can you explain in detail?

Sure I can but I never do someone else's homework.

> Thanks.

"Folkert Rienstra" <see_reply-to@myweb.nl> wrote in message
news:fv0f3m$mbr$2@textnews.wanadoo.nl...
> Eric Gisin wrote in
news:JMWdne-GPaDoFY7VnZ2dnUVZ_tSknZ2d@uniservecommunications
> > The enclosure has either an internal terminator or plug-in terminator.
> > Is it labelled SE or LVD (you have to look up the symbols)?
>
> It's obviously not SE as the internal drive is on the same segment and not
affected by it.
>

As I understand, 29160 has two independent segments while 19160 has only one
segment. The segment that the internal hard drive is on has nothing to do
with the other segment that the external SCSI enclosure is on.

As I said, all equipments are now U160 or better and the total length of
cables is less than 2 meters. The 29160 card only connects to two devices.
Both hard drives should have run at 160MB/s. What do I miss?

"Folkert Rienstra" <see_reply-to@myweb.nl> wrote in message
news:fv0f3m$mbr$3@textnews.wanadoo.nl...
> Ar Q wrote in news:MdOdnRSGdfG1C47VnZ2dnUVZ_gWdnZ2d@earthlink.co m
>
> > I am not sure what the Domain Validation is.
>
> > Can you explain in detail?
>
> Sure I can but I never do someone else's homework.
>

Well, I did find the definition at Adaptec's web site. It is a fancy word
for what I already know. Basically, the Adaptec card will decide and run at
the optimal speed after negotiating with all devices in the SCSI chain. Duh!