Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA Path: utzoo!linus!philabs!cmcl2!seismo!brl-tgr!tgr!GUBBINS@radc-tops20.ARPA From: GUBBINS@radc-tops20.ARPA (Gern) Newsgroups: net.micro Subject: Re: AT vs Z-100 - a myth Message-ID: <11149@brl-tgr.ARPA> Date: Thu, 30-May-85 10:43:26 EDT Article-I.D.: brl-tgr.11149 Posted: Thu May 30 10:43:26 1985 Date-Received: Sat, 1-Jun-85 10:49:21 EDT Sender: news@brl-tgr.ARPA Lines: 81 correction to my last message. The relaxed strobing statement should state, Intel designed the 8088/8086 to run with 3MHz memory at 5MHz with no memory wait states. This allows turboing, and 8MHz speed with 150nsec memory with no wait states. The following blurb is the independent benchmark results posted. Note that the same machine code was used on both the Z-100 and the IBM-AT and a standard 5MHz Z-100 beat the 6MHz AT 2 out of 4, close in the third, and lost fair and square in the forth. An 8MHz Z-100 (note that the results are interpolations, real values may be off by +- 1 sec) beats the AT 3 out of 4 benchmarks. The reason for the Z-100 putting up such a good show? That is the purpose of all these messages. The AT wait state is one reason, the IBM firmware, if like the PC, may be the other. Benchmark Blurb: 26-May-85 21:58:54-EDT,2901;000000000001 Return-Path: Received: from cit-hamlet.arpa by RADC-TOPS20.ARPA with TCP; Sun 26 May 85 21:58:36-EDT Received: from deimos by hamlet with DECNET ; Sun, 26 May 85 18:57:45 PDT X-ST-Return-Receipt-Requested: Date: Sun, 26 May 85 18:57:16 PDT From: atm%deimos@cit-hamlet.arpa Message-Id: <850526185657.002@deimos> Subject: Z-100 vs AT To: INFO-HZ100@RADC-TOPS20.ARPA Here is a bit of imput to the Z-100 vs. AT debate. I have run four benchmarks on both machines. The Z-100 has a 5 MHz clock, but an 8087 has been added (on a Hudson board). The AT has the standard 6 MHz clock and an 80287. The programs are the following: The Sieve of Eratosthenes, 10 passes (see BYTE, Jan 1983), which is entirely integer and logical operations. The Savage benchmark is solid double-precision floating point function calls (see Dr. Dobb's Journal, Sept. 1983 and Aug. 1984). Both of these have been run on a very wide range of computers, from a Cray to an HP-15 ! The third is INTSUM, which does double-precision arithmetic only, no function calls. The fourth is FOUR, which evaluates a Fourier series in single-precision, calling SIN(A) and doing indexing. All the benchmarks were compiled with MS-FORTRAN Version 3.2, using the 8087 mathematics library and the $NOFLOATCALLS metacommand, which is the combination that gives the fastest code. On the Z-100 they were run under Z-DOS Version 1.25, which is a few percent faster than MS-DOS 2.21, since it takes less time to service the clock interrupt. Run times are in seconds, and no allowance is made for loading time. The results indicate that a Z-100 with standard clock about ties an AT on any program which runs almost entirely in the 8087. (Note that the AT's 80287 runs with a 4 MHz clock.) If you multiply the Z-100 times by 5/8 to simulate an 8 MHz clock, then the AT loses on any program emphasizing floating point. However, it still wins on integer operations. Compiles and links don't use floating point, so the AT seems noticeably faster to use. The Compaq Deskpro, which has an 8086 and an 8087, both running at 8 MHz, should beat either the 8 MHz Z-100 or the AT. By the way, the AT can also be sped up to 8 MHz with a new clock crystal. I think the contestants should adjourn to the bar for a friendly drink. ________________________________________________________________________ Program SIEVE SAVAGE INTSUM FOUR Z-100 12.95 6.76 27.08 11.65 Z-100*5/8 8.09 4.23 16.93 7.28 AT 4.61 6.43 29.72 11.81 ________________________________________________________________________ Alan Moffet Caltech Note that the 8087/80287 are a supported option in both machines, and ZDS now supports 8MHz Z-100s, IBM only supports 6MHz ATs. Gern -------