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- Newsgroups: comp.sys.amiga.graphics
- Path: sparky!uunet!cis.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!eagle!bach.lerc.nasa.gov!fsset
- From: fsset@bach.lerc.nasa.gov (Scott Townsend)
- Subject: Re: Vivid 24 graphics card
- Message-ID: <1992Aug17.164849.5029@eagle.lerc.nasa.gov>
- Sender: news@eagle.lerc.nasa.gov
- Nntp-Posting-Host: bach.lerc.nasa.gov
- Organization: NASA Lewis Research Center [Cleveland, Ohio]
- References: <1992Aug13.002149.15986@maccs.dcss.mcmaster.ca> <64064@cup.portal.com> <andrey.713925244@harry>
- Date: Mon, 17 Aug 1992 16:48:49 GMT
- Lines: 60
-
- I'm not adding to this thread to discuss Amiga vs. SGI, but some statements
- made here don't agree with my understanding of how things are built. I have
- NOT seen the DMI board, I'm simply talking from the viewpoint of a Amiga, SGI,
- and parallel processor user.
-
-
- In article <1992Aug15.003630.23701@mnemosyne.cs.du.edu> dkennedy@nyx.cs.du.edu (Don Kennedy) writes:
- >
- >Note: the full blown system is rated at 28 MIPS, 160 Mflops. As a
- >Comparison, the Silicon Graphics 4K/480 VGX is rated at 280 MIPS, 70
- >Mflops. The SGI system costs $194,000. An Amiga 3000, 040 processor, and
- >Vivid 24 (full blown) costs $12,325.
- >
-
- This looks like CPU rates for the SGI. Most of the graphics power is in
- the VGX pipeline, and many (I don't know how many) MFLOPS of power it is.
- Maybe someone more familiar with the SGI internals could say just how much,
- but I don't think the above 70 MFLOPS figure is internal to the VGX.
- (I suspect the VGX to be greater than 70)
-
- For a fair comparison, you want to compare the relative CPU figures
- (i.e. r40000 vs. 68040) and the graphics pipeline figures (VGX whatever-is-
- in-there vs 32040)
-
- In article <andrey.713925244@harry> andrey@harry.ugcs.caltech.edu (Andre Yew) writes:
- >
- > I think it's rather pointless to compare something
- >like a 4D/480VGX to an Amiga with a Vivid board. First
- >of all, the 480 is much, much faster than any Amiga. Second,
- >if DMI think that they can squeeze 160 MFLOPS out of 4 40
- >MFLOPS processors, all the time, they'd best hang up their
- >business, find a willing research sponsor (of which there are
- >tons), and make huge, earthshaking discoveries in multiprocessing.
-
- I'll admit, I don't know where this 40 MFLOPS number came from
- (peak pipeline speed?, LINPACK? SLALOM? single/double precision?) but for
- graphics pipeline operations, which tend toward 'embarassing' parallelism,
- you can get close to linear speedup. In an Amiga system where the '30 or '40
- is updating a display list, etc and the DMI processors are just blasting pixels,
- I don't think quoting 160 MFLOPS for the processors on the board is
- out of line. A bit agressive perhaps ;-) (and certainly not without precedent)
-
- >Third, unless they've broken some laws of physics and economics,
- >there is no way they can reproduce the effects that a VGX system
- >can render.
-
- I assume we're talking VGX update _rates_, the effects are simply computations
- which the VGX is quite quick at. I could compute the same effects on
- my vanilla A3000, (or A1000!) just depends on how long you wait.
- (I'm using 'effect' here to mean what I see on the screen, is some other
- definition intended?)
-
-
- I didn't follow-up to advocacy since I'm after graphics/hardware information.
- Which system is better, etc. I'll leave for those in .advocacy
-
-
- --
- Scott Townsend, Sverdrup Technology Inc. NASA Lewis Research Center Group
- fsset@bach.lerc.nasa.gov
-