Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cbmvax!daveh From: daveh@cbmvax.commodore.com (Dave Haynie) Newsgroups: comp.sys.amiga Subject: Re: Attention Amiga (and Amiga to be) Users! Message-ID: <16010@cbmvax.commodore.com> Date: 21 Nov 90 13:59:13 GMT References: <1990Nov4.220612.21316@cbnewsl.att.com> <35605@cup.portal.com> <9537@jarthur.Claremont.EDU> <431@tlvx.UUCP> <85929@tut.cis.ohio-state.edu> Reply-To: daveh@cbmvax.commodore.com (Dave Haynie) Distribution: usa Organization: Commodore, West Chester, PA Lines: 56 In article <85929@tut.cis.ohio-state.edu> varun mitroo writes: >NeXT: .... > 1a. The Amiga has 16 bit NMOS custom chips for graphics and 8 bit sound. > Good, but very outdated. The wait states to access chip ram are > unbelievable. Right. They range from 0 wait states on up. > b. The NeXT has the DSP chip that is full 32 bit and performs at > 10 MIPS - much faster than even the 68030 at some things. The MC56001 in the NeXT is a 24 bit device, not a 32 bit device. It has a limited addressing range (not much of an issue anyway in the NeXT cube, since it has a fixed 24K chunk of memory). This device processes fixed point 24 bit numbers, not floating point, so while its certainly useful for sound processing, it doesn't do you much good with other jobs. > 2a. With DMA, amiga hard drives can achieve transfer rates of 1 MB/sec > b. The NeXT has 9 DMA channels that have a bandwidth of 40 MB/sec. > Transfer rates of their hard drives is 1.6 MB SUSTAINED going up to > 4 or even 8 MB/sec. The NeXTs don't run 8MB/sec sustained, simply because SCSI doesn't, either. The last set of hard disk (eg, not the 256K floptical, a real hard disk) benchmarks I ran into on the NeXT cube (either in UNIX Review or Personal Workstation, can't recall offhand) had real system performance peaking at about 450K bytes/second. You're taking the actual measured (in one case, it does go faster) performance of some Amiga above, and comparing it to some theoretical and rather questionably quoted specifications. You'd be good a writing add copy, but not fair reviews. The Amiga 3000's hard disk DMA controller transfers data at 20MB/s, which is the same speed the NeXT's bus runs at, as I recall (execpt for burst transfers, which, like in the A3000, go faster). Since standard asynchronous SCSI doesn't go much beyond 1.5MB/s, peak, the disk benchmarks don't, either. There are faster hard disks around, but neither C= nor NeXT is shipping them as standard equipment. The limit is the hard drives, and Amigas can use the same kind of drives as the NeXTs, Macs, Suns, and other SCSI based systems. > b. The NeXT has extremely high quality equipment. Everything about > the system shows - EXCELLENT keyboard, good mouse, heavy metal > enclosures for their computers (problems with the optical disk, > though). Of course, you have to wait and see what their cheap systems are going to be like. The original NeXT was a $10,000 machine. Our $10,000 Suns and Apollos had nicer keyboards than our el-cheapo versions of the same, too. > Varun Mitroo -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy Standing on the shoulders of giants leaves me cold -REM