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Re: DF <> SE Compatibility, Size compatibility with Debian, /HOME & other noobness?

On Thu, Apr 10, 2003 at 12:04:56PM +0200, Alexander Gabert wrote:
> Single Ended FAST WIDE=20MB/s 6 meter (used in recent workstations)

"Fast" Single Ended is 10Mhz bus timing and only allow 3m cable
(terminator to terminator).
Regular SE at 5Mhz allows 6m.
That's what sucks the most about SE SCSI: permitted cable length
is inverse to the bus frequencies. Differential (both LVD and HVD) 
doesn't suffer this problem. IIRC, they start having limitations
on cable length or number of devices above 40Mhz but not
nearly as severe.

> Single Ended WIDE ULTRA= 40MB/s 3 meter external cables (internal scsi of
> the C200 for example)disk size 4gb-9gb normally
> Single Ended WIDE ULTRA2=80MB/s 3 meters approx (fast, faster, ultra2 :-)
> you can find 18gig disks with ultra2 (also SCA connector)

Where did this info come from?
I'm pretty sure it's wrong.

Ultra SE 1.5m cable @ 40MB/s when 16-bit wide.
Ultra2 can only do 40MB/s when running SE mode (like Ulra SE).
Ultra2 LVD can do 80MB/s (16-bit wide)
Ultra3 LVD == u160 == 160 MB/s
Ultra4 LVD == u320 == 320 MB/s


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