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Article #161380827 affects speed of 80286? (July Byte)
From: john
Date: Sat, 04 Jul 1987 03:23
Date: Sat, 04 Jul 1987 03:23
34 lines
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1602 bytes
In the July issue of Byte they benchmark the 68020 and 80386 using (among others) the dhrystone benchmark. They also give figures for the 80286 as a comparison. The figure for an 80286 with an 80287 is 13% faster than a 80286 alone but as I recall the Dhrystone benchmark doesn't do any floating point so this would indicate that the 80287 somehow speeds up the 80286 non float instructions somehow - is that really the case or are the results bogus? The actual numbers given are: IBM PC-AT (8mhz) 1567.9 IBM PC-AT (8mhz)+80287 1748.9 Also elsewhere in the issue (the BIX stuff) someone claims the following results for the 386 (Dhrystones again): protected mode nonprotected Compaq 386 16mhz 5850 2380 386 Hummingboard 16mhz 6730 2777 386 Hummingboard 20mhz 8650 3571 Intel 386/20 6700 ---- The nonprotected mode was using Microsoft C in large model. The protected mode used Metaware 386 High C in small (4 gigabyte segs) model. 8650 is pretty impressive. Anyone have a capsule description as to why protected mode is so much faster? john
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!rochester!cornell!uw-beaver!ubc-vision!fornax!bby-bc!john From: john@bby-bc.UUCP (john) Newsgroups: comp.sys.intel,comp.sys.ibm.pc Subject: 80827 affects speed of 80286? (July Byte) Message-ID: <131@bby-bc.UUCP> Date: Fri, 3-Jul-87 23:23:05 EDT Article-I.D.: bby-bc.131 Posted: Fri Jul 3 23:23:05 1987 Date-Received: Sat, 4-Jul-87 19:41:37 EDT Organization: Burnaby, British Columbia, Canada Lines: 34