Picked up a pristine 386SX-16 system, but it doesn't look like the MHZ display was ever set up correctly. As I found it, the pins moving left-to-right on CN1 were connected +5V, GND, and then a yellow wire that was left hanging in the case. I've tried connecting this to the Turbo LED header and …

Success! Closing J10 was all that was needed. J6 open, J10 open wasn't a valid configuration. https://i.imgur.com/vCKTfVj.png There was an instruction sheet in the box. Should have though to check jumper settings, but my mind went right to the unpopulated ROM. There wasn't a socket originally and it …

Thanks, it's a byte-for-byte match with what I downloaded. Good to know I'm supposed to write as-is. I'll order a 256Mbit EPROM and play around with the jumpers, but I'm thinking this one's a goner.

Found a Trident 8900D ISA VGA adapter in-box at an estate sale. When I went to test, I noticed the lack of a VGA BIOS ROM, but decided to try anyway. 1 long + 8 short beeps at power on = video adapter test fail, not surprising. Soldered on a DIP28 socket. Found a VGA BIOS that looks like it should …

Don't fix a running system... Yeah, but 1024KB L2 cache would be sweeeeeetttt..... In regards to the expansion slot, I killed a PC CHIPS 386 board by tracing through it's proprietary slot with a multimeter. Now it beeps saying memory error in lower 64KB. Not gonna repeat that mistake with this …

I inherited a 486DX-33 system at work. UMC 481/482 chipset, 256KB L2 cache, AMI HiFlex BIOS 07/07/91 core. BIOS ID string is 40-0100-ZZ1211-00101111-070791-U480A/2-F. Looks to be this board https://stason.org/TULARC/pc/motherboards/D/DIAMOND-FLOWER-INC-486-486-33-50UCE-486DX2-50UCE.html . I'd like …