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From: "Hr.Ladavac" <lada@ws2301.gud.siemens.co.at>
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Subject: Re: SCSI bounce buffers
To: plm@xs4all.nl (Peter Mutsaers)
Date: Fri, 31 May 1996 13:04:33 +0200 (MESZ)
Cc: questions@freebsd.org
In-Reply-To: <199605310523.HAA02516@plm.xs4all.nl> from "Peter Mutsaers" at May 31, 96 07:23:14 am
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In his e-mail Peter Mutsaers wrote:
> 
> Hello,
> 
> I have an Adaptec 1542 and 16 MB RAM.
> 
> I want to get more RAM. This means I'll have to start using bounce
> buffers, or buy a newer SCSI interface (PCI, like Adaptec 2940).
> 
> Would using bounce buffers give a lot of slowdown? Is it really
> worthwhile to avoid it and buy a new SCSI interface. Also, would an
> Adaptec 2940 bring me a lot of extra performance when compared to my
> current 1542?

Well, it's a double edged sword--damned if you do, damned if you don't.

Bounce buffers *are* a hit.  16 megs vs. 20 or more is an even worse hit.
Your call :)

A PCI SCSI controller is almost an order of magnitude faster than the
ISA one.  OTOH, if you don't have any PCI slots on your MB...

/Marino
> 
> I hope someone can advise me on this matter. Thanks,
> 
> -- 
> ______________________________________________________________________
> Peter Mutsaers       |  Abcoude (Utrecht), |     "Quod licet bovis,
> plm@xs4all.nl        |  the Netherlands    |      non licet Jovi."
>