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From: "Jin Guojun[ITG]" <jin@george.lbl.gov>
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Date: Mon, 24 Feb 1997 20:20:12 -0800
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To: asami@vader.cs.berkeley.edu, mark@quickweb.com
Subject: Re: Memory speed of P6-200 (256k)
Cc: freebsd-hardware@freebsd.org, kuku@gilberto.physik.rwth-aachen.de,
        robsch@robkaos.ruhr.de
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>  * From: Mark Mayo <mark@quickweb.com>
> 
>  * > > 2097152000 bytes transferred in 27.298230 secs (76823735 bytes/sec)
>  * > > The motherboard is a P6NP5 (Natoma chipset) with 64 MB EDO-RAM.
> 
>  * > This is from my P6NP5:
>  * > 2097152000 bytes transferred in 25.741665 secs (81469167 bytes/sec)      
>  * 
>  * While we're at it, here are the results fom my Intel 440FX(Natoma) P6-200
>  * 2097152000 bytes transferred in 24 secs (87381333 bytes/sec)
>  * 
>  * My first generation PPro 150 from Digital only musters ~60MB/s..
> 
> Hmm, how come my new P6NP5 with P6-200 and 96MB RAM (parity mode) can
> give me only about:
> 
> >> dd if=/dev/zero of=/dev/null bs=1m count=1000
> 1000+0 records in
> 1000+0 records out
> 1048576000 bytes transferred in 18.359226 secs (57114390 bytes/sec)
> 
> I tried fiddling with the "RAS precharge" and "RAS to CAS delay" in
> the BIOS setups but the numbers hardly changed (always between 57MB/s
> and 60MB/s).
> 
> Did I get a "first generation" 440FX or something? ;(
> 
> Satoshi

Do not waste time to play this game. The "dd" is O.S. dependent code.
It does not give you what is real memory speed on your system. The result
from dd is really depended on the O.S. you are running. If you run 2.2 or
higher, you will get much better performance than 2.1.x.

440FX does have worse memory speed than Triton-{I,II}; even though P6 has
much better CPU speed, but the PCI controller (440FX) is worse.

hopefully this will more be clear.

-Jin