You are not logged in. Login Now
 0-24   25-49   50-59        
 
Author Message
chelsea
Memory Upgrade Mark Unseen   Nov 30 18:11 UTC 1992

Stupid question alert: I have a 386SX clone with 4 megs of memory and
would like to go to 8.  The motherboard will take up to 16.  Is this
a fairly simple thing with the appropriate sockets easily visible or
something only computer technicians should mess with?  Where is a good
source for memory chips?  How much should such an upgrade cost?
59 responses total.
daes
response 1 of 59: Mark Unseen   Nov 30 19:30 UTC 1992

Well, most of the newer systems have SIMM sockets.  If your PC has these,
then anyone who is comfortable with a screwdriver should be able to 
install them.  Good source and good price are beyond me...I work for
a company which sells and installs them in our systems, but I don't
think we would be the best price.
tsty
response 2 of 59: Mark Unseen   Nov 30 22:09 UTC 1992

Kinda a ball park - $40/Meg. A buck or two here or there, but that's
aboutwhat I've been reading - 
  
Oh, put some thing in the classified .cf - I'm *certain* there would
be a response .........
mcnally
response 3 of 59: Mark Unseen   Nov 30 22:25 UTC 1992

  If the motherboard was designed to use SIMMs, all you have to do
is pop them in (well, it's not always that simple, but it's pretty
close..)

  Though memory proices have gone up recently, I think $40/MB is still
a little on the high side..
mistik
response 4 of 59: Mark Unseen   Nov 30 23:44 UTC 1992

I don't know about too many boards, but some require that you fill a whole
bank, not just part of it.  So, the type of memory you are going to buy
really depends on that.  Prices vary on memory, however, $40/meg is pretty
close if you are going for 1MB x 9 SIMM modules.  Some boards are said not
to like 3 chip SIMMs, and also memory speed would matter on the price.

I recently quoted someone $40/MB for 1 MB 80 nsec SIMMs, but this changes
daily, even thruout the day.  If you can work with 4MB SIMMs, they seem to
cost slightly less per MB.
mju
response 5 of 59: Mark Unseen   Dec 1 03:47 UTC 1992

It depends a great deal on what the memory architecture is.  Best bet
is to open up the machine and count how many SIMMs it has; four
SIMMs probably means you have 1MBx9 SIMMs, while one SIMM probably
means you have a 4MBx36 SIMM.  If the former, you'll have to get
four 1MBx9 SIMMs and put them in the remaining SIMM slots on the
motherboard (assuming there are some; if not it becomes a bit
more difficult).  Shouldn't be difficult at all.
daes
response 6 of 59: Mark Unseen   Dec 1 16:29 UTC 1992

As this is a 386SX system, you have a 16 bit memory path, so I assume you
must put the memory in in pairs.  Given this assumption, the computer probably
has 4 1MB SIMMS currently and should support at least 4 more 1MB SIMMS.
chelsea
response 7 of 59: Mark Unseen   Dec 1 18:51 UTC 1992

Okay, so I'll start looking around for 4 SIMMS.  I've always had
pretty good luck with PC Connection and will check with them 
pronto regarding price and availability.  I take it no special
chip removal/placement tools are needed.  And what prayer do I say
to ward off static electricity so I don't fry the motherboard?
gunge
response 8 of 59: Mark Unseen   Dec 1 21:58 UTC 1992

Once you get the top off of the computer, touch the top of the power 
supply (while it's turned off but still plugged in to a grounded outlet)
to discharge any static electricity.
daes
response 9 of 59: Mark Unseen   Dec 2 06:01 UTC 1992

As service manager, I use the technique in #8 extensively...

Prior to the last year, and excluding the first, I was quite cavalier
about static.  As far as I know, I never lost any memory chips to
static electricity.
tsty
response 10 of 59: Mark Unseen   Dec 2 07:55 UTC 1992

   <<you don't remember, huh?>>   sfsf
  
The technique in #8 is the right way to start. And you can always
equalize the potential (discharge accumulated static) at any time
during the process. 
  
Without being s scare-monger, shuffling you feet on the carpet
while wearing synthetic cloths is a bozo-no-no. Discharge immediately.
  
Another extra-safety-precaution, if you are really worried - (but
don't be too worried, please) is: 
  
    Wear a metalic bracelet and obtain a fairly long alligator clip (a
wire with a spring-loaded clip on each end). 
  
    After the initial discharge, (ac plug still grounded in wall socket),
    stay in physical contact with the metal plates of the power supply 
    and unplug the computer from the wall. Then attact the alligotor
    clip both to your metal bracelet and also one of the screw-heads, or
    edge of a vent hole, in the PS cover. That provides continuous
    discharge throughout the process.
  
    Just before you remove the memory chips from their conductive
    plastic foam carrier, place and hold the plastic foam on the PS
    cover - the remove the chip adn insert into appropriate socket.
  
    Not a good idea to finger the exposed chip-leads either. 
  
    And again, don't shuffle feet.
  
That's about as paranoid as I can get without talking about humidity
and discharge mats and all that other stuff. Static electricity
is fun stuff to play with - and the events that create it must be
reversed to eliminate it. 
  
In one of the electronics classes I ahve taught, we were ablee to
generate, repeatedly, a 1/4"-3/8" spark. (0.250"-0.375") AS reference,
consider that your sparkplugs' gap is only about 0.042" and car ignition
systems operate around 30,000 volts (not static, but voltage none-the-less.)
  
   Happy chipping!
danr
response 11 of 59: Mark Unseen   Dec 2 13:09 UTC 1992

For safety, I would advise against simply using a wire with an
alligator clip at each end.  The wrist straps used in electronics
manufacturing have built-in resistors to limit current should the clip
or the person wearing the strap come into contact with a live wire.
Static is a real danger, but I don't think it's worth getting paranoid
about.
danr
response 12 of 59: Mark Unseen   Dec 2 13:11 UTC 1992

btw, I have such a wrist strap if anyone wants to borrow it.
klaus
response 13 of 59: Mark Unseen   Dec 2 13:31 UTC 1992

Yes there should be a resistor in series with the wire going from your
body to ground.  The value should be about 1 Meg-Ohm.  I don't use ground
straps myself.  They tend to get tangled in whatever I'm working on.  I
just touch metal, as mentioned above, be it grouded or not.  I'm only
concerned about _relative_ potential between me and whatever I'm working
on.  If we are both at, say, 100,000,000 volts, there will be no spark
between us.  (Though there might be a blinding flash between either of as
and ground!)
When passing boards or chips from one person to another, it is a very good
idea to first touch the other persons hand *before* touching the item being
passed.  Doing so will reduce any potential differance between both of you.
daes
response 14 of 59: Mark Unseen   Dec 2 15:35 UTC 1992

Ditto #13--This is what I do.
remmers
response 15 of 59: Mark Unseen   Dec 2 21:24 UTC 1992

All this laying on of hands stuff sounds awfully religious and
ceremonial to me.
rcurl
response 16 of 59: Mark Unseen   Dec 2 21:53 UTC 1992

They get a charge out of it. Say, Re; #10 and sparkplugs: one needs a much
higher voltage at high pressure, though the most important reason is
probably that they want more joules in the spark, which is required to
bring enough of the mixture locally to ignition temperature to get the
flame going. 
danr
response 17 of 59: Mark Unseen   Dec 3 02:13 UTC 1992

I'll give you some more advice... Don't pet your cats just before
installing the memory.  :)
mistik
response 18 of 59: Mark Unseen   Dec 3 06:14 UTC 1992

For a while, I used the touch first technique with one girlfriend, she would
zap me otherwise.
klaus
response 19 of 59: Mark Unseen   Dec 3 14:27 UTC 1992

On the lips?  (I've had that happen ;-)
daes
response 20 of 59: Mark Unseen   Dec 4 13:09 UTC 1992

It sure helps keep that "spark" in your relationship...

Mary, I checked out my prices...If you want to install it yourself,
I can sell you the memory for $40/MB.
chelsea
response 21 of 59: Mark Unseen   Dec 10 02:44 UTC 1992

I've spoken with Dave Simmons (what a guy!) and have a 
quasi-arrangement to have my machine's memory upgraded
by professionals who are static-free.  I'll probably see
to this right after the holidays.  With installation costing
only $5 a chip it's sounds like a good idea.

Thanks for all the information.
remmers
response 22 of 59: Mark Unseen   Dec 10 11:06 UTC 1992

The moral is that it pays to use people who are well-grounded in
their profession.
danr
response 23 of 59: Mark Unseen   Dec 10 12:25 UTC 1992

That's true. Neophytes are often all charged up and sparking with 
enthusiasm.
daes
response 24 of 59: Mark Unseen   Dec 11 04:11 UTC 1992

re 21:  Well, Mary, what do you mean by "what a guy!" anyway?  <*BLUSH*>
 0-24   25-49   50-59        
Response Not Possible: You are Not Logged In
 

- Backtalk version 1.3.30 - Copyright 1996-2006, Jan Wolter and Steve Weiss