Subject: Re: Physical memory tests?
To: Terry Moore <tmm@mcci.com>
From: Michael L. VanLoon -- HeadCandy.com <michaelv@HeadCandy.com>
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.
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Michael L. VanLoon michaelv@HeadCandy.com
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