rthurlow@van-bc.UUCP (Rob Thurlow) (06/16/87)
Well, I finally had to do it. I had run out of memory too often, and it
was not going to happen again. Besides, I had some overtime money! So I
got an Aerco RAM board from a local dealer*.
Installation was easy, but when I got it together, the screen was *not*
happy - the grey of the desktop was sparkling. The RAM test program took
one look at the stuff and promptly threw up three (sometimes four) bombs,
and I thought the RAM was questionable. No amount of jiggling of the
connectors would affect the screen appearance, so I called my dealer. He
apologised about not being able to meet me that day (at 5pm Saturday), but
met me Sunday morning at the store (!). We just swapped boards, since he
did not have a full ST there. So now, the screen looked worlds better, but
still has some problems. All my RAM testing programs are happy with the
stuff, but the mottled and decorative desktop bugs me.
So, my current thoughts are that the power supply at the board is not a
good clean +5V, but is marginal; that this causes the logic levels to be a
bit sub-standard when latched from the shifter, but not bad when the 68000
wants the data. I'm also wondering whether that other board was just a
little more unhappy with the logic levels than this one is. A solution to
this would be to run over a wire from the power connector; that would sort
of put a damper on the 'no-solder' solution, but I don't much care. Has
anybody on the net had any experience like this?
(*) - for you Lower Mainland people, the dealer was Gemini Sales in Burnaby.
, and I've had great dealings with him before.
--
------------------------------------------------------------------------
"There was something fishy about the butler. I think he was a Pisces, |
probably working for scale." - Nick Danger |
seismo----\ |
Robert Thurlow alberta----!ubc-vision!van-bc!rthurlow |
uw-beaver-/ |
------------------------------------------------------------------------med@drutx.ATT.COM (DrapalME) (06/16/87)
Regardinging the sparkling screen that you encountered after you installed your ram upgrade, it has been my experience that if these are caused by the socketed chips becoming loose. I have a procedure that I go through whenever I open my 520ST (which is very regularly, ask anyone around here ;-)): ALWAYS RE-SEAT all of the socketed chips, regardless. You don't need to remove them to do this, simply press them firmly into the sockets. I think that this should solve your problem. If not, you can always resort to the cheap keyboard fix (raise from edge of keyboard about 2-3 inches off of the table, then drop - its amazing how often this will fix those nasty socket problems). Myron Drapal ..!ihnp4!drutx!med
atwell@utah-cs.UUCP (Bart L. Atwell) (06/16/87)
I installed a solderless upgrade to my 520 this weekend and it worked great. The installation was easy and directions fairly straight-forward. This particular board has all the slots for upgrading to 4 meg. and has an optional clock. I'm told it is compatible with a piggy-backed blitter as well. I ordered it from Tech-Specialties for $179 (with .5 meg). Bart
grieggs@jplpro.JPL.NASA.GOV (John T. Grieggs) (06/17/87)
In article <4249@drutx.ATT.COM> med@drutx.ATT.COM (DrapalME) writes: > >... If not, you >can always resort to the cheap keyboard fix (raise from edge of keyboard >about 2-3 inches off of the table, then drop - its amazing how often >this will fix those nasty socket problems). Actually, there is a somewhat safer way to do the same thing - pick up the computer, grasp it firmly by the ends, and give it a bit of a twist. Stop before destruction occurs, naturally. This seems to do as good a job of seating the chips as anything else I have seen... _john -- John T. Grieggs (Telos @Jet Propulsion Laboratory) 4800 Oak Grove Drive, Pasadena, Ca. 91109 M/S 301-260A (818) 354-0465 Uucp: {cit-vax,elroy,chas2}!jplpro!grieggs Arpa: ...jplpro!grieggs@cit-vax.ARPA
dclemans@mntgfx.MENTOR.COM (Dave Clemans) (06/18/87)
running an Aerco/E. Arthur Brown 4 megabyte setup with no problems at all; it's been extremely solid. You should note though that I'm not using the Atari power supply; my ST is running off the same 150 watt XT power supply that runs my hard disks. If you install 4 megabytes in a "solderless" fashion into a 520, you'll at a minimum be powering 3 banks of memory chips (even though only two are being used) which potentially could put a stress on the power supply. As to the comment about the memory test program supplied by Aerco/E. Arthur Brown not working; I had that same experience. I used a public domain memory tester released by Supra Corp; that handled the 4 megabytes fine. Using the latest rev of the Aerco MMU adaptor board (you've got the latest rev if the MMU mounts "upside down") there is just enough room to piggyback a blitter chip on top of the 68000 cpu (if that turns out to be the ultimate upgrade method...) dgc