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From: sthaug@nethelp.no
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Subject: How to check synch transfer rate; can 2940UW do wide transfers with narrow device attached?
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Date: Sun, 09 Mar 1997 23:27:40 +0100
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I have a machine running 2.2-970215-GAMMA with an Adaptec 2940UW, which
is identified by the system as:

ahc0 <Adaptec 2940 Ultra SCSI host adapter> rev 0 int a irq 10 on pci0:16
ahc0: aic7880 Wide Channel, SCSI Id=7, 16 SCBs

Two questions concerning this:

1. Assuming a wide external device (in my case a Seagate ST15150W) *and*
a narrow internal device (IBM Ultrastar 2ES) connected at the same time:
Can the Adaptec still do wide transfers against the wide disk, or are all
transfers restricted to narrow?

2. How can I check what transfer rate is actually used for a particular
device?

Steinar Haug, Nethelp consulting, sthaug@nethelp.no