Subject: Re: Physical memory tests?
To: Terry Moore <>
From: Michael L. VanLoon -- <>
List: port-i386
Date: 08/03/1996 19:11:24
>ECC bits required scale as lg2(wordsize protected); for 64
>bits you need 8 extra; ditto for byte parity.  Note, though, that 
>if you are ECCing 64-bit words there are two practical problems:

>1)  32-bit writes require r/m/w cycles, which slows things down a lot.

As it applies specifically to this case of a Triton-2 motherboard: I
have heard, in fact, that they do indeed run noticably slower when
running with ECC enabled.

So, if you don't absolutely *need* ECC, you're probably much better
off with parity, anyway.  At least then you still know when something
breaks down, even if it isn't automagically fixed.

  Michael L. VanLoon                       
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