VOGONS


First post, by Gahhhrrrlic

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I ask for help a lot on these forums so allow me to give something back

I have a P133 with a SCSI controller, CT2740 Soundblaster 16 and half a dozen other odds and ends in this machine. I have formatted it and installed win95 maybe 100 times in the last year. Every time I did, the sound card and/or joystick and/or midi would fail to work or detect for some unknown reason, with my only clue being resource conflict errors like "I/O port 220H is not available. Check to see if something else is using it!". Can you really blame me for thinking that another card was stealing it or maybe the particular order in which I used my ISA slots was somehow to blame? This red herring was even further exacerbated when swapping ISA slots would fix the problem for exactly 1 boot-up, making me then think, "oh, the BIOS must be re-polling the devices but then it gets smart after 1 boot and takes my I/O address again".

Well, after every permutation of slot position and tearing the computer down to just a video card, come to find out the flippin jumpers that select the port address on the sound card just needed to be jacked off a bit on the metal posts. They must have developed an oxide layer of crap over the years and were intermittently telling the computer that either 220H wasn't really available or that my joystick wasn't really enabled.

Now, even though the moral of the story is to give your card a good overhaul of all moveable parts before considering other options, do bear in mind the obvious things like the card not being seated very well because the designer put a big-ass heat sink below the end of the full-length card, or that the PNP cards in your machine may indeed be writing to the same blocks of memory you're trying to use... things like that 😜

https://hubpages.com/technology/How-to-Maximi … -Retro-Computer

Reply 1 of 1, by Gahhhrrrlic

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Ok so it looks like corroded jumper contacts was only part of the problem. While indeed they do have an effect, my computer is now complaining about ALL lower DMA channels being unavailable, which makes no sense. Something else is FUBAR'd that I haven't found yet.

https://hubpages.com/technology/How-to-Maximi … -Retro-Computer