🚀 go-pugleaf

	The heat sink was attached by the cpu's prior owner, giving
little assurance of correct orientation.  Closely examine the cpu for a
gold dot, a gold +, or a flattened corner as indicatation of pin 1.  The
heatsink is attached by tape and can be removed with some effort.
Removing the heatshink should not be needed and is not recommended. 
Reattaching the heatsink will cerainly provide lesser heat conductivity.
That tape does an amazingly good job of transfering heat.  At 20mhz the
cpu shouldn't get too hot but it wouldn't be a good idea to test it with
your finger.  Unless your hiding from the authorities and wish your finger
print removed. :-)


Kevin


David Longley (David@longley.demon.co.uk) wrote:
: I have a Cyrix Upgrade Chip with heat sink attached to it. I'm 
: considering replacing the Intell 386-20 in a COMPAQ DESKPRO 386-20
: (circa 1988). 

: Unfortnately, I can't see any orientation edge on the CYRIX Chip.
: There's the CYRIX labelling on the underside of the CPU, but....
: Is there sdome convention re the orientation of the labelling 
: on the underside of CPUs regardless of manufacturer? How can
: one tell which way to insert the chip? 

: There *is* a white paint mark on the heatsink and I have indicated 
: its relative position by the 1 on the CYRIX chip relative to the 
: text on the underside.

: Similarly, on the Intel chip, I have marked where the notch is 
: relative to the text on the underside.

: Intel Underside     Cyrix Underside 

:  ------------1       ------------ 
: � 37434420AA �      �1992CyrixUSA�
: � MALAY   51 �      �      JAPAN �
: � B          �      �            �
: �            �      �            �
:  ------------        ----------- 1
:                                 suspected
:                               orientation pin
:                        (white paint mark on heat sink)

: Has anyone got one of these CPUs lying about without a heat sink on top 
: which gives some idea of the pin one location?

: -- 
: David Longley

: Longley Consulting                                                  London, UK
: Behaviour Assessment & Profiling Technology,
: Research, Data Analysis and Training Services,
: Small IT Systems                                http://www.longley.demon.co.uk