VOGONS


First post, by Alexa

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Hi Everyone,

I am new to building computers and I thought I'd be ambitious and decided to build my husband's dream computer, a 486!

I am building with a(n) :

- Intel 486 Dx4 at 33 MHz x 3
- (2)x4 MB of SIMMs (EDO RAM) which is 8 MB total of EDO RAM
- Abit AB-PB4 Rev 1.2 motherboard
- new power supply

I have been fiddling with the computer and I was able to get into the BIOs. When I got into the BIOs it still wouldn't boot after a restart and would hang. However, I was trying to make the system work and played around with the jumpers and floppy drive. Now the system doesn't display anything anymore. I have been using a motherboard manual and I am looking to install a sound card, I/O controller card, and a video card. The video card is a PCI (ET 6000).

Any guidance would greatly be appreciated! I have attached a picture here 😀 and I'll be more than happy to attach more pictures. 😀

Thanks!

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Last edited by Alexa on 2022-05-17, 01:42. Edited 2 times in total.

Reply 1 of 14, by Cuttoon

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Hi, that looks like a neat little board and fairly modern for a 486.
Usually, this is a good resource: https://www.ultimateretro.net/en/motherboards/85#downloads

General advice, for troubleshooting,

- Respect ESD precautions.
- Check the PSU adapter and motherboard plug for good fit and that no pins are bent, maybe apply some contact spray
- Reduce entities. Only minimum, so, VGA card, one RAM module
- Consider removing the board from the case and set it up on a table, maybe a book below it.
- double check all the jumpers and make a good photo without power cable, cpu cooler or vga card, post that here - maybe you've missed something.
- If it does not display anything, listen for beeps, those can tell you what is wrong:
https://www.computerhope.com/beep.htm#award

Of course, feel free to try & error: different PCI slots for the VGA, different RAM modules in one or the other slot.

Once it works, consider getting 16 MB of RAM for it, should be around ten bucks in an auction or fair BIN offer.

Good luck!

I like jumpers.

Reply 2 of 14, by AngryByDefault

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Hi! Nice board indeed!

To what Cuttoon said I would add removing and reseating your memory SIMMs.

Also, if by chance, you have a less valuable video card (i.e. an run of the mill Trident) use that untill you have your basics under control so you're not unnecessarily risking a good card.

Cheers.

Reply 3 of 14, by Alexa

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Hi everyone, I spent a few hours trying to figure out what was wrong. I couldn't even get the system to post. I checked all the jumpers and swapped the parts and cables around. I ended up buying a new board on eBay. I will be updating this post soon. 😀

Reply 5 of 14, by Disruptor

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Basically it's a good idea to write down the existing jumper settings after a purchase before changing them. You also may take a detail photograph and post it here (even now!).

Before running a received mainboard it is a good idea to check the capacitors.
When running it for the very first time, it is useful to listen to the BIOS outputs.
Best way is a port 80 diagnostics card. You will see first diagnostics outpots here.
Easiest way and highly recommended is to connect a PC speaker. You will hear later diagnostics outupts here.
Third way is to install a VGA graphics card and nothing else. You may see a post screen here.

Reply 6 of 14, by H3nrik V!

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Is EDO RAM a thing with 486? Didn't that first come into play in Pentium era? As in, would the chipset recognize it?

Link from Cuttoon's post shows 36-bit memory config? Isn't that odd? Or is it parity RAM?

[Edit] checked the manual, which clearly states that EDO is supported and also lists RAM as 32-bit 🤣

Please use the "quote" option if asking questions to what I write - it will really up the chances of me noticing 😀

Reply 7 of 14, by RandomStranger

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I think almost all 486/socket3 boards use EDO that also had PCI slots. The platform has been kept alive by clone manufacturers like AMD and Cyrix for years after Intel abandoned it. The last 'modern' CPUs released for it were 5x86 models from Cyrix and AMD in 1995.

sreq.png retrogamer-s.png

Reply 9 of 14, by Anonymous Coward

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I think it's more accurate to say that certain steppings of late 486 chipsets "support" EDO RAM.
I have seen different opinions if it's actually worth the trouble to bother.

"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium

Reply 10 of 14, by PARKE

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Anonymous Coward wrote on 2022-05-18, 07:36:

I think it's more accurate to say that certain steppings of late 486 chipsets "support" EDO RAM.
I have seen different opinions if it's actually worth the trouble to bother.

It is actually a good point I think.
A Diamond Fastbus VLB board manufactured in the first half of 1993 that I once had ran on EDO ram. According to the web it came with Chips & Technologies F84021; F84025; F82C721 chipset which more likely than not did not take advantage of the superior properties of EDO ram - it just 'supported' it.
As far as I can find the advantage of EDO became only available via the Intel 430FX in 1995.

Reply 11 of 14, by Alexa

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Hi everyone. Thanks for all the tips and advice. I got the first motherboard to post consistently! It turns out the RAM was bad. Good thing two more sticks of 2x16MB SIMMs came in the mail today.

Now I am unable to get past the BIOS. The only adjustment I made was to Enable the Boot Up Floppy Seek. Once I hit "Enter" the screen shows a black display, and that's it. Am I doing something wrong?

https://drive.google.com/file/d/1t0QAjD2pBM5i … iew?usp=sharing

Reply 12 of 14, by waterbeesje

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You may check the battery. When turning the system off, the system uses the bios to keep the data. With some too low voltage, but high enough to save some of the bits, data may end up corrupted with a reset or power cycle.

Since you're using the cr2032 replacing is as easy as it gets, as is measuring the voltage.
What happens if you remove the battery and turn the system on without it?

Also, just to be sure, you may reseat everything twenty times to 'break' traces of dirt and corrosion. Also you could clean the contacts with isopropyl alcohol (and make sure all has vaporised before turning the thing on again)

Stuck at 10MHz...

Reply 13 of 14, by Alexa

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@waterbeesje, thanks for the tips!

since my last post just 3 hours ago.. I have burnt my power supply and destroyed it. :c The power switch came into contact with the power supply and completed the circuit because I was being careless. There was a loud pop and it tripped the circuit breaker of my house. I'm praying none of the other parts fried. I have place another order for the power supply and it will be coming sometime early next week. 🤣🤣☹️😭

THANK YOU for all those that took their time to help me with this build. I am extremely grateful! 💕I will continue to update this post during this build. Thanks everyone! 🙏😊

Reply 14 of 14, by Alexa

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waterbeesje wrote on 2022-05-18, 22:17:
You may check the battery. When turning the system off, the system uses the bios to keep the data. With some too low voltage, bu […]
Show full quote

You may check the battery. When turning the system off, the system uses the bios to keep the data. With some too low voltage, but high enough to save some of the bits, data may end up corrupted with a reset or power cycle.

Since you're using the cr2032 replacing is as easy as it gets, as is measuring the voltage.
What happens if you remove the battery and turn the system on without it?

Also, just to be sure, you may reseat everything twenty times to 'break' traces of dirt and corrosion. Also you could clean the contacts with isopropyl alcohol (and make sure all has vaporised before turning the thing on again)

I can check the battery once my new power supply comes in. The cr2032 battery was brand new so it should work. I was told to replace it from the very beginning. I can try another new cr2032 battery. I'll also clean the contacts with isopropyl alcohol and reseat everything in my next session with the 486... that is everything didn't blow up afterall. 😆