13 Mar
1998
13 Mar
'98
12:59 p.m.
> mobo for a busted SIMM socket.
Also on
cheapie motherboard the contact fingers were too soft and had
to bend the board other way when installing the simms.
I've seen this stated on several newsgroups as
well, but I can't
understand why it's impossible to solder a new SIMM socket onto a
motherboard. You can break up the old one, desolder the pins one at a
time, fit a new one (I've seen them on sale in the UK), and solder it in.
Takes about 10 minutes. I've done it before now.
That's what I would do if
the latch is broken.
There is a myth doing the rounds that it's
impossible to use a soldering
iron on PC parts. I don't know where it came from, but it's 100% false.
Duh! Truly 100% folkore story! :)
BTW, I've seen a few non-name SIMMs with dry
joints between the
surface-mount chips and the carrier board. Resoldering those was an
entertainment...
Not that only one, I have few cheap simms with bad plate-thoughs.
Wow.
Probably more on-topic for this list is a 30 pin SIMM
that I have in my
spares box. It's 256K*9, using pin-through-hole chips (normal 41256 DRAMs
in 16 pin DIP packages). It does use the normal SIMM pinout AFAIK.
There was one oddball design of this simm that used soldered DIP's
but one chip is outside one side of the socket with traces around the
cutout for the one latch! That was used heavily samsung or hyduani
built Peecees in that early 90s. Few of that simms had chips went
bad from group of 3 machines. Very high failure rate and chips is
hyundai made.
Of course I repaired them by removing all 9 chips and test them one
by one on other PC with socketed memory until dud is found.
Then resolder them all in! In these days it was appox 20 a stick for
256k x 9 80ns.
Ditto on one hyperion portable after 21 chips later
bad memory chip was found. Not fun that all of this are soldered in
and that was 2 years ago.
Did bent few Dip's in few machines including a compaq 286 deskpro,
the motherboard is one of a kind, takes 72 256k chips to make 2mb.
Took a while to find the guilty because hard to see ic with
bent leg.
Jason D.
email: jpero(a)cgo.wave.ca
Pero, Jason D.