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From: shwake@raysnec.UUCP (Ray Shwake)
Newsgroups: comp.unix.xenix.sco
Subject: Re: Shadow RAM for BIOS
Keywords: performance improvements 386 Xenix 2.3
Message-ID: <129@raysnec.UUCP>
Date: 3 Nov 90 18:32:41 GMT
References: <107963@convex.convex.com> <1990Nov1.093716.28337@bbt.se>
Organization: IRS/CI - Technical Solutions Branch
Lines: 14

pgd@bbt.se writes:

>I don't think that is true. We have machines with four different
>versions of Micronics motherboards. (one old TTL 20MHz, one newer
>20Mhz, one TTL 25MHz, and some ASIC 25MHz) None of them reserve the
>shadow RAM specially. So I find it very unlikely that a later model,
>the 33MHz motherboard does that. They all have dip-switches to reserve
>memory, but Xenix is ignoring all that, and is using all memory.

	Don't know if this is universally the case. I'm running Xenix/386
on an NEC 386/20 (C/T chipset, Phoenix BIOS) which reserves 384k. Neither
Xenix nor ISC UNIX (which I also run on this box) access this memory, as
verified at boot time. Of course, if someone *does* know a way to access
this memory, please advise!