nelson@cygnus.Kodak.COM (Bruce D. Nelson) (10/13/90)
Have any of you atari-st netters had experience with the JRI SIMM board for memory expansion on a 1040 (or 520). I've heard about its exisitence, but have seen no ads or reviews of it. -- Bruce Nelson | Phone: (716) 726-7890 Rochester Distributed Computer Services | Internet: nelson@cygnus.kodak.COM Eastman Kodak Company | Rochester, NY 14653-5219 | Standard disclaimers apply
rcb@netcom.UUCP (Roy Bixler) (10/15/90)
In article <1990Oct13.145829.18783@kodak.kodak.com> nelson@cygnus.Kodak.COM (Bruce D. Nelson) writes: >Have any of you atari-st netters had experience with the JRI SIMM board >for memory expansion on a 1040 (or 520). I've heard about its exisitence, >but have seen no ads or reviews of it. > There was some discussion about it a few months ago on the net. The fact that the JRI board takes SIMM's and that the discussion was positive made me 'take the plunge' and try to expand my 1040 ST's memory to 4 Meg. What I encountered was a nightmarish cycle of 'my computer doesn't work' and 'take it back to the store'. Since some people out there are probably saying "I've had no problems with this", let me describe the problems I had. First, I would turn the computer on and, after a few minutes of use, the objects on the screen wouldn't line up as they used to. This makes it especially hard to read text! The technician at San Jose Computer told me that the memory chips were overheating and 'fixed' it by removing the RF shielding. The original problem went away, but then any data I tried to write to my hard disk was scrambled. After talking to John Russell himself, it was found that the DMA chip was of IMP origin (i.e. bad stuff). To conclude this cycle and my patience, the DMA chips were replaced and there was still a problem (forgot what it was, but different than the two previous ones). I finally achieved 4 Megs. of memory by purchasing an STe. The technician might have aggravated the problem by not being scientific in isolating the problem, but that is a moot point now. If I were a hardware person, I would have investigated this more thoroughly. Since I'm not and I don't have the time, the only conclusion I can draw from this experience is you should be aware of the origin of your DMA chips and ventilation can be a problem. >-- >Bruce Nelson | Phone: (716) 726-7890 >Rochester Distributed Computer Services | Internet: nelson@cygnus.kodak.COM >Eastman Kodak Company | >Rochester, NY 14653-5219 | Standard disclaimers apply Roy Bixler netcom!rcb@apple.com
kawakami@volcano.Berkeley.EDU (John Kawakami) (10/16/90)
In article <1990Oct13.145829.18783@kodak.kodak.com> nelson@cygnus.Kodak.COM (Bruce D. Nelson) writes: >Have any of you atari-st netters had experience with the JRI SIMM board >for memory expansion on a 1040 (or 520). I've heard about its exisitence, >but have seen no ads or reviews of it. The installation was pretty simple, but I'm sure that there are people out there who would get confused: the pictures are scrunched full of info and not everything is flat-out stated. If you know what an address bus is, and know what the various electronic components look like, the installation should not be a problem. If not, then get someone else to do it. The upgrade itself has little to go wrong with it: just make sure the wires slip around the inside of the ST ok. However, I have had problems with HEAT. It's pretty crowded in a 520ST and I noticed that the chips get HOT. The JRI board covers part of the 68000 and other chips, and also brings in some RAM chips and makes the whole shebang heat up like a toaster. I had problems with the RAM flaking out on me: the screen would fill up with garbage on from one bank of SIMMs overheating.* I "cured" this by removing the RF shielding and raising the board off the motherboard (with a cardboard standoff). This seems to be a not uncommon problem from the mail I have received. Another cure are to get cooler RAM (I have "Magic SIMMs" Maybe the answer is to get "better" name brand SIMMs with Micron or Japanese chips) another is to get a fan, another is to get a STe. * SIMMs come 8 bits at a time, so you need two SIMMs for the ST: a 16 bit word size machine. The SIMMs sockets are angled so the SIMMs "lie" on top of each other like bacon. I figured it was the bank caught under the other SIMM that got hot and flaked. When I swapped SIMMs, the garbage showed up on the same half of the 16 bit word. John Kawakami kawakami@ocf.berkeley.edu ucbvax!ocf.berkeley.edu!kawakami Amateur crank! My Atari Macks!