Well, I have a few 486 parts that should be here sometime tomorrow, and I found an old case with a dusty OPTi 82C496 CHIPS 486 mobo in it, but I can't tell what it supports for hardware. I'm pretty sure it only can handle a 50MHz CPU. Wish it had more info written on the board.
Jumpers can be pretty confusing but if it's new enough to be socket 3, it has to support faster. 50mhz is going to be the highest bus setting. I know with my old systems, I have to set all the jumpers for 33mhz and then there's one last jumper that controls multiplier.
BTW, if not already, once you're sure the jumpers are set right, if the board still stays black, you also might want to try booting with another video card just to make sure that's not a problem spot as well.
Thanks for the advice on the video card. I got yet another board (same as the first one I was using) to test the rest of the parts on and I momentarily got a video signal... just enough to tell me that there was and A: drive error or something like that. I only had the ram it came with, the weak VLB video card, and of course the 100MHz CPU.
I got very excited and began to attach the drives and now it will not display. The A: and B: drive lights are on constantly as soon as I turn it on as well so I must have somehow screwed up the cables on them.
🙁 I guess I'm back to the proverbial drawing board.
Congrats on getting it to POST. I think checking the cables and making sure you didn't install a card or some chips or a cable wrong will be an easier task than setting the jumpers up was.
Ok, I unplugged every drive in the computer and got a video signal back.
All that shows up on the screen is: Award BootBlock Bios v1.0 Copyright (c) 1995, Award Software, Inc.
BIOS ROM checksum error
Detecting Floppy drive A media...
Drive A error. System halt
Correct me if I'm wrong, but I think I need to change the battery. 😖
A dead CMOS battery can cause problems. However, they're rarely the cause of failure to show video. If the battery is dead, it'll most likely cause some issues but I think the reason for no post is how the drives were hooked in. Make Make sure that any IDE drives you plug in are jumpered right too.
The BIOS chip got corrupted. You'll need to reprogram/reflash the BIOS. That's what the bootblock is for and why it's asking for a floppy. It's searching for a copy of the BIOS, to restore itself.
http://www.birdjanitor.com/bootblock.html
You also can reflash it in another board and the put it back in.[/url]
Thanks for the tip. I searched for a couple hours for a BIOS download and couldn't find anything for this motherboard so I took the chip and switched it with the one from the other board (identical boards btw) and got the same message. 🙁
I searched for a couple hours for a BIOS download and couldn't find anything for this motherboard so I took the chip and switched it with the one from the other board (identical boards btw) and got the same message.
OK, just so I'm clear here... first of all, we're still talking about the Soyo 4SAW2 from the OP, right? I ask, because BIOSes for that one aren`t difficult to find at all.
Secondly, the other board you borrowed the BIOS chip out of, was it working before you swapped the chip? In other words, do you know if the BIOS on that one was good?
They're also available here: http://www.elhvb.com/mobokive/archive/Soyo/bi … /486/index.html
Weird that you have two exact boards with corrupted chips... If the chips are still good, you only need a floppy and a copy of the bios to restore them.
1. Make a DOS floppy, with only IO.SYS, MSDOS.SYS, COMMAND.COM (delete the rest), a copy of the BIOS and AWDFLASH.EXE.
2. Then create an AUTOEXEC.BAT with only this line inside:
AWDFLASH.EXE xxxxxxxx.BIN /CC /CD /CP /QI /R /PY /SN
(replace xxxxxxx.bin with the name of the downloaded BIOS)
Then let the machine boot with the floppy on the drive. It should restore itself. Wait while it's doing this, if it works, it should reset itself later.
Hope I get that right.
Weird that you have two exact boards with corrupted chips...
A little too weird, which is why I asked for clarification on the details... That error can be caused by other hardware problems.
I worded my last post wrong. I could find the .bin file but I can't seem to find the awdflash.exe file. If I understand, it's usually bundled with the same download as the BIOS.
Yes both boards were the SOYO 4saw2. I'm not certain that either chip is good, but I figured that I'd give it a try.
Ok I just tried switching things back around and for some reason neither chip will allow POST on the first board but both will come up with the same BIOS checksum error on the second board.... I feel like I'm missing something obvious here.
Ok I just tried switching things back around and for some reason neither chip will allow POST on the first board but both will come up with the same BIOS checksum error on the second board....
That's sorta what I was suspecting. BIOSes generally don't just get corrupted at random... it's usually a result of a failed attempt at flashing. Since both chips work in the other board, it's not a corrupted BIOS ROM. Sounds like you have something else wrong with that one board. I'd check it over carefully, looking for physical damage... broken components, damaged traces, corrosion in chip sockets, stuff like that.
For future reference, though, on the matter of awdflash.exe, it's not a board-specific utility, so you can get it elsewhere. Older boards often tend to need older versions of it, so it would probably be worthwhile to keep a few different versions handy. Alternately, Uniflash will work for most boards.
I just took a closer look at the board and discovered that the a few of the standoffs broke away, allowing the board to touch the metal of the case at the edge. 😳
The only other time I can remember that happening (286 computer that my brothers and I worked on when we were kids in the 90s), I was lucky enough that it didn't cause permanent damage, but I'm afraid that might not be the story with this one. 😢
I should be able to do more testing sometime tomorrow.
wrote:I just took a closer look at the board and discovered that the a few of the standoffs broke away, allowing the board to touch the metal of the case at the edge. 😳
The only other time I can remember that happening (286 computer that my brothers and I worked on when we were kids in the 90s), I was lucky enough that it didn't cause permanent damage, but I'm afraid that might not be the story with this one. 😢
I should be able to do more testing sometime tomorrow.
Dammit...
Sorry to hear that. Were the standoffs laying on the bottom of the case?
I'd suggest you test both of the outside the case, they might still work.
If they touched the very edge of the board, chances are nothing critical was shorted. Often the very edge of a motherboard is 'loose space', so to say.
There might be hope for the first board, but I bid my final farewell to the second one. 😵 Back to square one.
Most of the standoffs were plastic clips that snapped free and allowed most of the bottom of the board to touch the case.
Clearing out for the other board right now and wishing I had just gone with the Shuttle motherboard/case combo.
Ok. After taking a long break due to flu, snow, etc. I tested a few of my hard disk drives and discovered that the one that I thought was fine actually is broken. no computer will even recognize that it's connected. So I went digging through my supplies and discovered an identical drive that appears to be in good condition... that explains some of the problems I had in the past. There is hope. 😐
:edit:
For some reason when I insert the floppy disk to flash BIOS, the drive won't light up and seems to make no attempt to read the disk. Any thoughts?
I usually have trouble getting floppy drives to work first time. Try different cable orientations. Is the bios set for the right type of floppy drive? If you set the bios to test the floppy drive on boot-up [so you get that kind-of throat-clearing sound errr-huhhh-hmmmm] then you get to know a bit quicker than waiting to test a floppy in it.
Try another floppy drive. Try a different cable.
Btw, I wouldn't try to flash a motherboard if I can't even get it to work properly first, you'll run into problems sooner or later. It means you're trying to flash a precious motherboard while doing something wrong.
I tested several floppy drives (TEAC, panasonic and i'm not sure what the others were) and all have the same result. I changed several cables with no result either.
Just so I'm clear, the red wire on the floppy cables should line up with Pin 1 always, right?
I thought the floppy port might be damaged but there's no visible signs of wear, cracks, or missing pins.
In other thoughts I tried the drives and cables on the 50Mhz machine and I could get into BIOS but it kept changing the floppy to a 720k 5.25" drive B even though there is no such drive even connected to the system. I'm really confused right now, I've never had so much trouble with any systems before. 😢
P.S. I really appreciate everyone's time and patience. 😀
