First post, by Ace
Soon after I picked up that 486 motherboard I asked about, I now find myself with two new motherboards to mess around with:
-A 286 motherboard loaded with 640KB of RAM, a 10MHz Intel 286 and a Cyrix 287XL
-A Socket 4 motherboard with a 60MHz Pentium on it and the maximum 512KB of cache
The 286 board works fine, but the Socket 4 motherboard has problems. First problem: the battery leaked so much, it destroyed a trace linking a component to the keyboard port. I've bypassed that broken trace with a small piece of IDE ribbon cable, but have since discovered a bigger problem.
After I fixed up the broken trace, I loaded the RAM slots with some 72-pin SIMMs and discovered a bigger problem. As soon as I flick on the power on the power supply I have hooked up to the motherboard, the power supply shuts off. To me, that sounds like a short, and sure enough, my multimeter confirmed this. The short is between -12V and Ground, and I cannot figure out where this short is. I know the ISA slots have -12V on them and there's a tantalum capacitor on the -12V rail that goes to Ground, which leads me to these questions:
-If a tantalum capacitor goes bad, can it cause a short?
-What else could use -12V on a motherboard like this?
If pictures are needed of the motherboard, I'll post some later today.
Creator of The Many Sounds of:, a collection of various DOS games played using different sound cards.