Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!crdgw1!sixhub!davidsen
From: davidsen@sixhub.UUCP (Wm E. Davidsen Jr)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 387-20 Async vs. 387-25 Sync performance?
Message-ID: <483@sixhub.UUCP>
Date: 12 Feb 90 05:10:10 GMT
References: <2340002@hpldsla.HP.COM> <10643@june.cs.washington.edu>
Reply-To: davidsen@sixhub.UUCP (bill davidsen)
Organization: *IX Public Access UNIX, Schenectady NY
Lines: 19

In article <10643@june.cs.washington.edu> luong@grace.cs.washington.edu.cs.washington.edu (Luong La) writes:
| Yo FLOP's guru,
| 
| I owned a 386-25 computer w/ option that I can either install an async 387-20
| or 387-25 sync. math coprocessor.  My question is :) does the 387-25 sync offers
| a good bang for my bucks?  I heard that a 387-25 sync can offer about 
| 0.6 to 1 MFLOPs, how about 387-20 async?  

  I think you mean that you can set the clock for 20 or 25MHz, since I
never heard of async or sync versions of the 387 (particularly in the
part catalogs). Typically the f.p. is 20-30% of the total CPU, even on
math intensive applications. If you want better performance you need to
go to IIT or Cyrix (sp?) for 387 clones which run faster at the same
clock speed (perform ops in fewer clocks).
-- 
	bill davidsen - sysop *IX BBS and Public Access UNIX
davidsen@sixhub.uucp		...!uunet!crdgw1!sixhub!davidsen

"Getting old is bad, but it beats the hell out of the alternative" -anon