Hi,
when I poweron this motherboard I hear 3 beep without video output. On the keyboard I could see three led poweron and poweroff and after tha beeps.
I tried to replace the DIPP memories with another 286 worked motherboard but obtain same results (same chipset headland and CPU 286/16 harris). I tried only with anothe worked memory SIMM but same results.
Does anyone have any ideas?
thanks
Badly corroded traces in top picture from the battery and also all along the top. 2 ISA slots on the right also full of leaked battery contents.
Bottom pic also shows corrosion of traces. Middle pic also shows further corrosion.
That motherboard looks pretty trashed to me, it'd be beyond my capabilities to repair if I owned it, but others who are more skilled with soldering could probably give it an attempt.
Without knowing the brand and model of the motherboard (or at least the BIOS maker) it's difficult to know for sure what the 3 beeps mean. Depending on the BIOS, they can range from "keyboard problem" up to "memory problems".
The traces lined in red are critical no matter who made the board, they supply to the ISA slots.
Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun
Thanks guys. I'll try to check the traces
The three red line are good.
I removed two resistors and four pin jumpers and I found 7 traces around battery interrupted. In the red circle the traces.
Next days I'll try to repair.
I repaired the seven broken traces but obtaining the same three beeps error when started. I thinking there is a bad IC because when in the first time I powered blowed a capacitor. I think that I can put in the trash. 🙁
Old tantalum caps blow up all the time, they simply go bad and it's not an indication that there's a bad IC. Seeing that the corrosion is quite spread, it's more likely is that you missed one or more bad trace or via, possibly under the KBC, RTC chip or one of the first ISA slots. Can be a lot of work to diagnose, and almost impossible if you don't have a vacuum desoldering station. Still, I wouldn't put it in the trash; rather keep it for parts or give it away to someone who might be willing to try his luck.
Try to replace or remove from the board those memory chips (V53C104BP70L). If will not help then check if there are any broken connections between the SIM memory slots and the XT12 controller. You can use any multimeter for this. Most likely (99% probability) that the problem is either with these chips or a damaged track on the board or maybe a short circuit due to a bent leg at the bottom.
https://theretroweb.com/motherboards/s/iqs-jli#downloads
https://theretroweb.com/motherboards/s/dfi-286-20
Are similar models.
OP sold the board years ago, this post is a dead.
PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K
