Path: utzoo!utgpu!watserv1!watmath!att!dptg!mtune!klh
From: klh@mtune.ATT.COM (Ken Hinds)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 8087 Coprocessor
Message-ID: <673@mtune.ATT.COM>
Date: 12 Jul 90 13:31:23 GMT
References: <1990Jul11.172043.525@bigsur.uucp>
Organization: AT&T BL Middletown/Lincroft NJ USA
Lines: 25

From article <1990Jul11.172043.525@bigsur.uucp>, by mussar@bcars53.uucp (G. Mussar):
> In article <169@evtprp0b.UUCP> tea6219@evtprp0b (Terry E. Acker) writes:
>>I have an XT with a V20 processor running at 8/4.77Mtz.  What speed
>>coprocessor do I need.  If there are different speed 8087s, can I
>>use a 4.77Mtz 8087 and set the system speed to 4.77?  What if I run
>>the system at 8Mtz with a 4.77Mtz 8087?  Will it work?  Will it
>>overheat?
> 
> If you plan on always running at 4.77 MHz, no problem. If you switch to 8 MHz,
> chances are the system won't even boot/run. This is based on trying the same
> experiment with a 4.77/10 MHz XT. YMVM. Even if if does boot/run, the 8087
> (which normally runs pretty warm) will run VERY hot and this will decrease its
> life significantly.

Well, I have a dual speed 8088 micro processor in my Leading Edge 
Model D and I have added an 8087 math coprocessore but, it is listed
as an 8087-2  which implies dual speed... Sorry I don't recall the
manufacturer but, I'm sure you could find it if you ask for it specifically.

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Kenneth Hinds                _             _
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UUCP:  ...!att!mtune!klh     /--' _  ,_    /--/ @ ,_   __/                
       klh@mtune.att.com    /  \_</_/) )  / \/ /_/) )_(_/\/)_
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