Doug Partridge wrote in message
<35A### [at] lawsonappcomputaseduau>...
>Why the price difference between the alpha running linux and the alpha
>running nt?


The Alphas are actually two different processors.  The 21164A (also known as
the LX version) is the "full" version and the 21164PC (also known as the SX
version) is an alpha minus the onboard L2 cache and at most 1meg cache on
the motherboard.  The 21164PC is a much smaller die size and therefore much
cheaper to produce.  So it costs less.

>There was also only one second difference between linux and nt, does
>this make linux really worth it?

It seems Linux makes a big difference only in x86 systems for POV-Ray.

I'm still trying to figure out why the 21164A didn't beat the 21164PC by a
larger margin.  In most software I have written the 21164A is about 5% to
10% faster.

21164A
    onchip L2 and 2 meg cache on motherboard
    128 Meg ram
    Ultra Wide SCSI hard drie
    64 bit Linux

21164PC
    no L2 and 1 meg cache on motherboard
    64 Meg ram
    E.IDE hard drive
    32bit Windows NT

All that should give the 21164A an edge.  The only plus for the 21164PC is
that it can access the cache on the motherboard faster (I think 2
nanoseconds if I remember right).  I need to look into the intervals of POV
more to really what is going on.  That and I'm tired of the division by
zero's (which is an alpha version problem).

Also on Linux vs. NT I've noticed that Linux has more consistant runs.  I
was making an animation under NT where the parse took 45 seconds for the
first frame.  After that the parse time kept getting faster and faster.  At
about the 100'th frame the parse time was down to 19 seconds!  It stayed
there after that.  Under Linux it was around 20 seconds  through all the
frames.  NT has alot of odd behavior that way.

>I usume the prices are us dollars
Yep.  Sorry, about that.

mark

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