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From: "Serge A. Babkin" <babkin@hq.icb.chel.su>
Message-Id: <199605161047.QAA13555@hq.icb.chel.su>
Subject: Re: EDO & Memory latency
To: narvi@haldjas.folklore.ee (Narvi)
Date: Thu, 16 May 1996 16:47:46 +0600 (ESD)
Cc: hackers@freebsd.org
In-Reply-To: <Pine.BSF.3.91.960516130639.25743B-100000@haldjas.folklore.ee> from "Narvi" at May 16, 96 01:19:46 pm
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> 
> 
> On Thu, 16 May 1996, Serge A. Babkin wrote:
> 
> > I have just tried lmbench and the numbers it gives are looking
> > slightly strange for me. It shows memory latency upto 500ns while
> > I have 60-ns EDO memory in a Pentium/75 box. Okay, its external
> > clock is 25MHz, this gives 40ns, one wait state, it gives another 40ns,
> > it gives 80ns, but why the overhead is over 400ns ? 
> 
> The external bus of the Pentium 75 should be 50Mhz. It is 1.5x50, not

You're right, I was wrong. So, the guestion gets yet more interesting :-)

> 3x25. 60ns EDO sounds like an overkill for a Pentium 75 though...
> I would use a quicker processor and (120) with ordinary memory 
> (fast-page, 70ns) - but the likes may vary. 

I just got them for the same price as ordinary memory and of course
I choosed EDO. It costed me $125 per 8M SIMM.

-SB