🚀 go-pugleaf

boggart**@hairyolaf.force9.net wrote:
: I have an Adaptec 1542CF running a Micropolis 3243AV drive on my
: machine (a 486) and was wanting to know if, when I upgrade to a ninja
: Pentium, this will drag the system down.  The Adaptec is only ISA and
: as it, and the drive, are only Fast SCSI-II, I am concerned that I
: would be doing an injustice to a 200MMX system with 64Mb RAM.
:
: Does anyone have any comments?

The 3243AV sustains 4 - 7 MB/s, while the 1542CF will allow only
1.2 - 3.6 MB/s for most systems. Heck, a good recent EIDE drive is
faster than any SCSI drive on an 1542!

: Also, if I changed the Adaptec to something newer, such as the 2940U
: or 2940AU, and then added a SCSI-III drive to my setup would it still
: work?

Yes.

: I remember reading somewhere that if I have a Fast SCSI-II and
: SCSI-III ultra wide drive attached, the SCSI-III one will only perform
: as a SCSI-II because it uses the lowest common denominator.

Nonsense. Transfer speed parameters are negotiated *per device*,
i.e. a narrow Fast SCSI-2 will transfer bursts at 10 MB/s and a
wide Ultra drive will use 40 MB/s bursts when connected to the
same (wide Ultra) host adapter.
Note however that few drives break the 10 MB/s barrier for *sustained*
transfers yet.

: I would be grateful for any assistance as I don't want to be stuck
: with hideous disk performance, but at the same time I don't want to
: buy a SCSI-III disk if it won't make a difference!

Todays top 7200 RPM drives are approx. 30 % faster than your 3243 -
the 10000 RPM Seagte Cheetah is even twice as fast - at a premium.

Virtually PCI host adapter will give you a significant
performance boost - without having to buy a new disk drive.


--
Ralf.