Subject: Re: slow 21164 Alphas (Re: Raptor 3 rendering service)
From: Andrew Hofman <[email-masked]>
To: Multiple recipients of list <[email-masked]>
Date: Tue, 23 Jan 1996 13:12:34 -0500

>>essentially two of the earlier 21064 Alphas on a single chip. This makes
>>each Raptor 3 twice as fast as a 275 MHz Carrera, Aspen or similar machine.
>
>If you had a good 21064a based system, you would know that is not true.
>I fairly thoroughly benchmarked a *300MHz* 21164 based EV5, and these
>systems are MUCH faster than the 266MHz Raptor 3. On average, it was
>only 1.75x faster than my 21064a clocked at 300MHz. I'd venture to say
>that your 266MHz 21164 is closer to 1.5x the speed of a good 21064a
>system. Also, based on my findings and the current costs, I found it
>silly to even think about buying a 300MHz 21164. They are way too over
>priced for their performance.
>  
>  Mark Thompson

Check out the July 1995 issue of VTU, page 50. Tim Doherty directly compares
a number of systems using the same scenes, including a Raptor3 21164/266 and
a Carrera Cobra 275. Two of these scenes are Texture Examples and Space
Fighters. I was able to duplicate his Raptor 3 figures, with the exception
that all of my times were exactly one second longer (or some fraction
thereof, since that's the smallest unit LightWave shows). Even with that
one-second slowdown, it still meant an average speed difference of 204% vs.
the Cobra. I can't say what the difference would be compared to another 275,
like an Aspen. The 21064 system you tested must have been exceptionally good
to yield that kind of performance vs. a 21164/300.

Why the one-second slowdown? I can't say, but I remember hearing from other
Raptor 3 owners at the time who had tried the tests and were mystified by
the same thing.

By the way, exactly how much faster *was* the EV5? I agree that the price
just now is far greater than the added performance (from any vendor). I'll
wait until something comes out that REALLY kicks the 266's butt! 

I just keep thinking "radiosity," and cringing.

  
Andy Hofman
LumaQuest Productions           
Animation and Dual Raptor 3 Rendering  
[email-masked]
513-643-7333