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From: Andrew.Gordon@net-tel.co.uk
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Date: Sun, 26 Jan 97  2:40:12 +0000
X400-Content-Identifier: Re: Overdrive qu
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To: mcgovern@spoon.beta.com
Cc: hackers@FreeBSD.org
In-Reply-To: <199701260123.UAA00264@spoon.beta.com>
Subject: Re: Overdrive question...
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> I tried dropping an Evergreen Overdrive processor in to my 486/33 tonight.
> Although the system booted, and started ok, programs starting crashing
> because the symbol "___sF" is not defined (or a similar error). 
> 
> Can anyone give me the rundown on this, and if there is any way to get it
> working so I can run the overdrive chip? I just hate to send it back - it
> seems like such a neat toy to keep an aging system running.

I have two systems with these Evergreen upgrades in them, so there is
definitely no fundamental problem with running FreeBSD on them.

One of the systems was previously a 486/66, and the upgrade works fine
at the 4x clock setting.  It also works whether configured for writeback
or writethrough - even though this machine has an AHA2842 VLB SCSI
controller, which I would have expected to be upset by write-back.
However, the WB/WT setting doesn't seem to make any difference to
performance either, so maybe somthing on the motherboard is disabling it. 

The other machine works fine when configured for 3x clock, but won't even
boot when configured for 4x - I suspect some BIOS problem.

Have you tried changing the 3x/4x link on your one?