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From: se@zpr.uni-koeln.de (Stefan Esser)
Date: Thu, 11 Jan 1996 13:39:15 +0100
In-Reply-To: iain@nwpeople.demon.co.uk (Iain Baird)
       "Re: anyone there using AMD's 133MHz chips?" (Jan 11, 11:32)
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To: iain@nwpeople.demon.co.uk
Subject: Re: anyone there using AMD's 133MHz chips?
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On Jan 11, 11:32, Iain Baird wrote:
} Subject: Re: anyone there using AMD's 133MHz chips?
} Stefan Esser writes:
} > On Jan 10, 18:31, Dmitry Kohmanyuk wrote:
} > } Subject: anyone there using AMD's 133MHz chips?
} > } are there any problems/opinions on them?  It is worth to choose them
} > } over 120MHz ones?  (i.e., time make world on both)
} > 
} > According to some reports I read, the 5x86 is not
} > significantly faster than the 486DX4/120, but it
} > has the advantage to work well on PCI only mother
} > boards, which prefer a 33MHz bus clock (and don't
} > like a 40MHz clock at all :-)
} 
} I'm running a DX4-120 on a GA-486AMS PCI-only motherboard.
} This can clock PCI at CPU/2.  By default, with CPU at 40MHz,
} PCI runs at 20MHz.
} 
} However: I have tried setting CPU:PCI to 1:1, so PCI is clocked
} at 40MHz, and everything seems to work fine.  So far at least.
} I have an AHA-2940 and a Diamond Stealth 64 (S3 968).  I haven't
} done any benchmarking to compare the performance.
} 
} Any comments on the wisdom of this?

Well, this has got nothing at all to do with wisdom.
But a lot with luck ;-) 

PCI chip sets are designed for a 33MHz upper limit, 
and I'd be afraid of overheating the expensive S3 
or AIC chips, and the mainboard PCI chip set as well 
(eek, all soldered in :)

I'd rather spend a few $ on the 133MHz variant, even 
if it is no faster than the DX4/120.

But that is a matter of personal taste ...

Regards, STefan

-- 
 Stefan Esser, Zentrum fuer Paralleles Rechnen		Tel:	+49 221 4706021
 Universitaet zu Koeln, Weyertal 80, 50931 Koeln	FAX:	+49 221 4705160
 ==============================================================================
 http://www.zpr.uni-koeln.de/~se			  <se@ZPR.Uni-Koeln.DE>