I've never updated the BIOS on a 486 before. But for Pentium Class and newer each manufacturer has a particular process possibly even their own tool. I would never try to flash a BIOS with a random tool unless it was the specific one the manufacturer specified.

Me neither about any older BIOS. I'm rather paranoid to say the least and would not want to mess up this working mobo, but I figured it was worth asking. I can live with the time, I just changed it to 1994, it's the SD card thing I'd like to get resolved if there's a continued problem.

I think my flaky SD card results are because I unplugged my ribbon cables and swapped them out. It's working again, I can boot up and so on, so I'll just keep my fingers crossed that it holds. If I do encounter more problems and the BIOS is not an option/solution, I was thinking that another I/O card might help.

Anyways, I know I'm going to have more questions, but I don't want to keep on creating new threads -- especially for minor stuff I should have remembered.

You'd need a stand-alone EPROM programmer and preferably a new EEPROM to program a new BIOS. Such a board won't have flash circuitry and will use the older EPROM chips which require UVC to be erased.

Ahhhhh, thanks. That's not something I'd want to do right now. 😀 But looking forward, those EPROM boxes are affordable and Phil has a video on flashing a BIOS.

I'll stick with what I can handle. I'm going to order a new IDE cable online and then another I/O card if problems happen again.

Who?

If you ever go after an EPROM programmer I'd recommend the TL866, it's cheap and supports most chips. You can skip the EPROM eraser and grab a new EEPROM which can be electronically erased in the programmer, this way you can keep the original BIOS chip on hand in case anything goes wrong (though you can read it in the programmer and keep another backup if you want to be extra safe) as well as skipping out the nasty UVC crap you need to work with EPROMs if you have to flash them again. So for future reference, a good EEPROM to use would be a 29EEE020 - but never try to flash them in the motherboard on the off-chance it actually does try to write to them, because the programming voltages probably won't match and it will not end very well at all. There are other EEPROM parts that are identical (That one is a Winbond or an SST I think) - I seem to think Atmel make a part with the 28C256 part number that would also work. Whatever, I'm sure someone here will help you if you ever decide to go that route.

You're probably right to leave it as a last resort though, playing with the BIOS is always a pain in the ass and if things go wrong, they usually go really wrong.

Unfortunately I can't help with the SD card issue, I've never been a fan of translating on the fly like that and have found CF to be the better format in such systems. But on the off-chance, you don't have a CD-ROM plugged into the same cable do you? That can cause problems as the adapters often aren't designed to be used this way.

You can also sometimes drag the boot sector back by getting a floppy with the installed version of DOS (Or if you run Win9X, use the appropriate boot disk for that OS) and running FDISK /MBR but this is hit-and-miss and is best left until you're certain it won't boot and if you don't mind the small risk of losing the partition entirely - this isn't very likely at all, but it is possible in some weird circumstances.

I flashed the Bios with my Willem Eprom Programmer in my Lucky Star 486 mobo. Mine also has the Y2K bug and there is no way to get around that. It's not always
the Bios that's the problem, but sometimes the Real time clock IC.
I also tried a program called bios patcher and modbin which does cpu microcode updates but that didn't help.
All You can do is pick a Year where the Day and Month lines up, as in Today is Sat 28th May. Use 1994 and just pretend whilst on Your PC that that's the case.

Yeah, to be honest, most of mine are set to the year the system would probably have existed new... Or they were, I guess a few years on they've moved forwards by now.

Actually, I'm glad you mentioned it because I haven't turned the clock back on my Memphis machine for a while and if it passes a certain date the OS bricks itself.

Thanks HighTreason, very helpful. I do have a CD-Rom on the same cable, so now that you mention it that could be the issue. My only problem, is that I only have one IDE channel available. The SB16 in this system doesn't have an option. I went the SD card route since I have so many of them laying around, but if all else fails I'm going to move to a CF adapter.

Sorry, this is Phil and here's the video I was mentioning:
https://www.youtube.com/watch?v=b_dEcShoR5Y

Imperious,
Thanks! Is the Real Time Clock replaceable by chance out of curiosity? I set my clock to 94 and it's holding, so I can live with it. 😀

The potential issue there is that CF adapters aren't always any better at sharing the wire. It the worst comes to the worst, you might be able to find a VLB Host Adapter which has two IDE channels. I have a version of the board in the second link, the MB-4DUVC, and use such a card cards with a CF adapter on Primary and a CD-ROM on secondary. Without access to such hardware this can be irksome on such machines, before that card I had to juggle two I/O cards in the same machine and it caused a metric tonne of problems over the years. Sound cards with IDE can work, but sometimes only with specific drives and it might use more Conventional memory. As luck would have it, most things that want the CD-ROM will use high memory anyway (EMS or XMS) so either way that works best with some kind of toggle - but I guess that's a bridge to cross when you get to it. The important thing for now is trying to make it work and seeing if that actually is the problem.

Ah, I see, that guy. I'm sure he's familiar for some reason but I can't place my finger on it... *cough* coward *cough*
Oh, well, I'm sure he makes some good stuff anyway.

MCGA wrote:

Imperious,
Thanks! Is the Real Time Clock replaceable by chance out of curiosity? I set my clock to 94 and it's holding, so I can live with it. 😀

I really don't know. That would require doing a lot of research if the information is still out there. It's usually a IC on the motherboard, best left alone I reckon.

I do have the Freetech 486F38 bioses here.. First is a modified one (should support bigger harddisks (didnt tested it myself) and an original Rev G bios that solves that Y2K bug..
I dont know exactly where iam stored them on my computer.. But if you want that have them i can look for it..

@HighTreason,

I'm going to look around for a VLB I/O with more than one port. I had forgot about the drive limitations on the SB cards and pretty much everything else you mentioned. Thanks again!

@Imperious,
Thanks. Yeah, I'm going to leave it alone.

@Robin4,
Awesome|!! I'd like it eventually if it's not a hassle? So if you stumble across it by accident. 😀 I'll just need to buy an EPROM Programmer, which I'm planning on after I get a few more things in order.

You can get away without a CD drive in a 486, especially if you have a CF or SD card that you can access from the outside of the case.
I install my games then apply No CD cracks. I can then just swap the CF cards depending on what I want to play.
You do loose CD audio in games if that's a deal breaker though.

The other thing I recommend is connecting it to the network for file transfers once you have the base OS installed

If you're going that route, you can even use SHSUCDX to mount CD images, apparently anyway, I have not tried yet. Sounds like it would work out well though, given you could use a fairly large card and just swap out images on a second system with any bog-standard USB card reader.

I started using those CF adaptors that fit in a blank slot and allow access to the card from outside of the system fairly recently... I ain't looking back.

Networking is always worthwhile, just be aware that the old system might not be able to access a newer one, but it works the other way around almost without fail.

Awesome, thanks! I was wondering about getting by without a CD if things don't work, and it was a question I wanted to ask about. 😀 I don't even have a CD to Sound-card analog cable at the moment.

My system has been working for days now. It boots up just fine and I can read a CD, but I haven't done any installs to see if it's stable. I'm waiting for my Floppy Emulator to arrive from Amazon( I'm not on Prime, so they take their time. ), so that I can start installing software and drivers.

As for networking, the 486 I bought came with a 3Com Etherlink III. I found the drivers I believe the other week, so I just need my FE to arrive; I'm paranoid about pulling my SD card out to write to it, because of the problems I encountered. I'm going to have to look into this, so hopefully it's a straight forward process. I've never networked any of my early nineties PCs outside of a serial-linking.

And I'm really considering getting a CF adapter that takes up an ISA slot. BTW, do you guys have any suggestions on mounting the SD Card Adapters? I have one like http://www.ebay.com/itm/SD-SDHC-SDXC-MMC-Memo … yEAAOxyHIlTaLLP.

Robin4 wrote:

I do have the Freetech 486F38 bioses here.. First is a modified one (should support bigger harddisks (didnt tested it myself) and an original Rev G bios that solves that Y2K bug..
I dont know exactly where iam stored them on my computer.. But if you want that have them i can look for it..

Could you please share your bios for MB 486F38 ?

I have found this information but , the files it self are not available any more ;/

38X-G.BIN -- AWARD BIOS Ver. G. for 486F38x/F39x/F41x - 38x-g.bin
F38 Award Manual -- Motherboard manual in PDF - f38award.pdf

THX