First post, by 8bitbubsy
I just got a miroCRYSTAL 20SD (S3 Vision864 2MB , old card revision), and I found out that my system won't POST if my VLB Multi-I/O card (PTI-255W v1.2, Winbond chipset) is also connected. With an older S3 805 GPU, I have no issues whatsoever.
Any idea what could cause this? I've tried different RAM, restoring default BIOS settings, changing VLB waitstates on both motherboard and GPU+I/O card, cleaned connectors, tried a different CPU (486DX2-66 -> Cyrix DX2-66), etc. I also tried to disable everything on the Multi-I/O card, but still no POST. The only thing that works is if I remove the multi-I/O card.
EDIT: Also tried to swap the cards, tried all three VLB slots.
The motherboard is a "SIS 486G 3.3/5V Ver:E".
- CPU: 386DX-33 (no external cache)
- RAM: 4MB 70ns FPM
- VGA: Cirrus Logic GD-5424 1MB ISA
- Audio: SB Pro 2.0 + GUS classic 1MB
- ISA PS/2 mouse card + ISA USB card
- MS-DOS 6.22 + Win 3.1
- MR BIOS