[comp.sys.mac] SIMMs installation problem

crist@unc.cs.unc.edu (David Crist) (06/07/89)

Recently, our department has received a shipment of High Profile 1m SIMMs.
I was the individual assignned to install them.  Everything was going well 
until I ran into a different looking MACII.
	Let me explain.  It seems that all of the MACs in our building have
'white' SIMM slots and the installation into these has been simple.  This
particular mac has 'black' SIMM slots and it is quite difficult to fit the
SIMMs into the rack.  
	QUESTION:  Does anyone know about this problem?  I can't believe that
Apple has a plot to make my life more difficult.  (Maybe they have) Anyway,
APPLE or anybody, if you have any idea on what the problem might be, please
send me E-Mail.  And if the problem is that big a deal, I'll summerize.

Thanks
david crist
	crist@dopey.cs.unc.edu
Univerity of North Carolina
Chapel Hill

twakeman@hpcea.CE.HP.COM (Teriann Wakeman) (06/10/89)

The SIMM slots on my Mac+ were black AND I had trouble trying to install
High profile RAM from MacProducts USA. I pushed a little too hard trying to
get a socket arm to lock down over the SIMM & the arm broke :*<

The problem was the lower row of DIP pins interfering with the
lower lip on the socket. The 'cure' other then replacing the socket
with another type is to clip the lower row of pins that stick below the 
board.  

CAUTION: use standard anti static techniques
         cutting pins may cause a mechanical shock to inside the package
            connections 
         Make sure that no matal chips bridge the space between pins

One strategy - use a special low static solder sucker to remove the
solder to the lowest row of pins. If the board has plated through holes,
clip the pins at the lower board surface, If not pltaed through, bend
pins flat against board away from adjoining traces {the pins will
probably need to be shortened}.  Resolder connections using a solder iron
approved for CMOS soldering.  The modified SIMM should fit without any       
problems.  You run the risk of destroying a chip or the board if you
are not experianced with this kind of operation. Be careful!! be antistatic

Another strategy - get rid of the SIMMs intended for this Mac {return, trade,
use in another machine, mail to me {;*)} } & get some SMT {lo profile}
SIMMs for this mac.

TeriAnn
twakeman@hpcea.ce.hp.com

nghiem@ut-emx.UUCP (Alex Nghiem) (06/11/89)

In article <430108@hpcea.CE.HP.COM>, twakeman@hpcea.CE.HP.COM (Teriann Wakeman) writes:
1> The SIMM slots on my Mac+ were black AND I had trouble trying to install
1> High profile RAM from MacProducts USA. I pushed a little too hard trying to
1> get a socket arm to lock down over the SIMM & the arm broke :*<
1> 
1> The problem was the lower row of DIP pins interfering with the
1> lower lip on the socket. The 'cure' other then replacing the socket
1> with another type is to clip the lower row of pins that stick below the 
!> board.  
...
!> Another strategy - get rid of the SIMMs intended for this Mac {return, trade,
!> use in another machine, mail to me {;*)} } & get some SMT {lo profile}
!> SIMMs for this mac.

There has much discussion about MacProducts SIMMS on the net in the past. The
major complaint is problem like yours--MacProducts SIMMS are non-standard
size and manufacture and cause the SIMM sockets to be broken. 
MacProducts will not 
honor the warranty if you so much as scratch excess solder off a pin. Many
of us ex-MacProducts customers recommend that you stay away.