Subject: Re: AMD 586 dx4 133 support
To: -Vasily Lewis <>
From: Michael L. VanLoon -- <>
List: port-i386
Date: 09/10/1996 19:18:12
>  That would be me that flipk is buying the board/chip from.  I think it
>might be important to note that for all discernable purposes the chip is
>nothing more than a 133mhz 486.  The whole naming scheme for the chip
>(which is officially Am5x86(tm)-P75) seems to be just a marketing scheme
>for AMD.  All the digs on the chip can be seen here if you're curious: 

It's not *completely* marketing.  At least how they look at it.

The reason they consider it "more than" a 486 is because all "real"
486s have 8KB write-through cache.  And, all "real" 486s are either 1x
(SX, DX), 2x (DX2), or 3x (DX4 -- also a marketing anomoly) clock.
The "5x86" has a 4x clock and a 16KB write-back cache.  So, they were
trying to make a point -- that it's faster than any "real" Intel 486.
They just picked a really bad way to do it.  Of course, they probably
did that on purpose.

This was all further muddied by Intel adding a 16KB write-back cache
to the 486DX4 (the "write-back enhanced" 486).

  Michael L. VanLoon                 
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