VOGONS


First post, by dacow

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In my pile of retro hoarding treasure/junk, I have a 486 PC Chips board. I've had a few light attempts at trying to fire her up but nothing seems to happen. Just wondering if there's anything else I can try or assume it's a dead board and throw it away.

Board looks almost like this except socketed cache chips. So probably an earlier model.

The board came with jumpers set to what looked to be for an Intel DX2/80 CPU, I can't get the blasted heatsink/fan off to tell what it is. I plugged 1, then 2 72 pin SIMM's in and no post. The only card I had in was a working VGA ISA ET4000. I then grabbed a PC Speaker from one of the other machines and plugged that in and nadda. Reversed the polarities on the speaker just incase but still no beeps. PSU fires up, cpu fan spins but nothing. I grabbed a DX33 CPU set the jumpers and still no beeps or anything. Took the video card out and no beeps.

Dead?

Reply 1 of 11, by Tetrium

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Your SIMM's are FPM? (not sure if your board actually supports EDO). Have you tried powering up the board without any memory?

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Reply 2 of 11, by dacow

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Tetrium wrote:

Your SIMM's are FPM? (not sure if your board actually supports EDO). Have you tried powering up the board without any memory?

To be honest I have no idea whether the SIMMS are FPM or not? I pulled them from a P166 board. This time round I haven't tried powering up the board without memory, I can't recall if I did it last time I played with the board. IF the memory was bad/faulty/not compat you would think it would still beep no?

Reply 3 of 11, by kixs

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It should beep. But this is not always the case.

Pentium almost for certain has EDO ram which is very rarely supported on 486 boards. So you should get FPM 72-pin memory from somewhere. One piece is enough for testing.

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Reply 5 of 11, by dacow

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Thanks guys, will try it again, I do have some other 72pin modules non pentium era so I'll give those a go!

edit: Hmm tried it again with some 30pin SIMM's and still no good. I think it's definitely a gonner

Reply 6 of 11, by devius

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If your board has 30pin SIMM sockets it may be configured to treat those sockets as the first memory bank. If that's the case it won't boot without any SIMMs in there. Try looking for one of those resistor networks (usually named RN1, or RNA1, or something like that) near the memory sockets that can be used to change how the board assigns memory banks to the available SIMMs. If your board doesn't have this printed on it, then you need a manual. If you can't find a manual it will be hard to guess.

Edit: Oops... I missed your edit. I guess it's dead then.

Reply 7 of 11, by dondiego

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Basta! 😉 Are you sure the psu is good and the speaker works? Then you should try without ram and graphics card, if there are no beeps mobo is dead. But you shouldn't have changed the cpu.

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Reply 8 of 11, by devius

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dondiego wrote:

Then you should try without ram and graphics card, if there are no beeps mobo is dead.

I have some (old) motherboards that don't boot and don't produce any beeps if they don't like a particular graphics card. Older boards like this one are just quirky and don't behave like we expect them to. I guess that's part of the fun 😀

Reply 10 of 11, by dacow

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The PSU and speaker definitely works, pulled the speaker from my 386 and PSU was used to test another board of mine earlier. Devius: I've tried two different video cards and still no cigar.

Racoon: I'm fairly sure the voltage jumpers are set correctly. If you look at the last pic on the ebay link I posted in the beginning; there is a jumper called JP35 which is either on or off. On is 3V and off is 4V, you can see it to the right of the CPU in the last pic on the ebay link.