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Blown Motherboard from ATA-100 Cables?
Dragan Lazin asks: "I recently bought a couple of rounded ATA-100 cables from an online store; very ingenious actually and they have a nice color: blue ;-) Problem is, when I installed the cables, 16 capacitors on my motherboard blew - right between the CPU and the parallel port header. This is an Abit KA7-100 mobo. What the hell causes this kind of damage? I'm trying to get a refund and a new mobo from the company. Did anyone ever experience this?"
There isn't enough voltage or current in those cables to blow a cap off of a motherboard. We are talking about high/low signalling. Likely on the order of 20 to 50mA tops. Even beyond that, there are no capacitors connected directly to the IDE signalling lines.
How do we blow up caps? 1) power up a tantulum cap backwards. Not possible with a bad IDE cable for the reason above... no caps connected to the lines. 2) apply a huge voltage to a low voltage capacitor. Likely the caps on a motherboard are around 6.3V caps, so this is possible. But again, there are no caps on the IDE lines. Not gonna happen.
Hence, blowing caps off of the motherboard (assuming that it actually did happen...) was not caused by the cables. The only was to possibly do this was to plug in your cables from the powersupply to the motherboard wrong. In this case, it is possible to get GND and +V backwards in this case.
Don't blame the cables, blame user stupidity.
Actually, I doubt that this is even a real question. Sounds more like a troll that got posted by Cliff.
- It's anarchy baby. Suck it up.
Capacitors blow up from too much heat, which for a DC power supply filtering capacitor implies too much voltage. Capacitors are in parallel with the power supply. Something put too high a voltage across the capacitors.
Unless I'm really confused, the highest voltage on the IDE connector is only 5 volts, and all of the pins on the IDE connector are either ground or are compatible with 5 volts. You can hurt the logic chips and the power supply by shorting stuff on the IDE connector, but you won't blow up the capacitors.
The reason ide cables have traditionally been ribbon-shaped is to minimize cross-talk. Perhaps the round cables use some sort of pair-twisting scheme, or maybe they use shielding. Or perhaps they just decided that cross-talk wasn't really as much of a problem as the engineers originally thought.
"Any fool can make a rule, and any fool will mind it."
--Henry David Thoreau
Well, on a cheap motherboard, it could be possible that the IDE's V+ and ground aren't regulated seperatly from the main power regulator on the board. A short across the two could cause the power regulator to heat up very quickly, and the radient heat could spell trouble for the nearby caps. I can't imagine that it would all happen instantly though. There also could be a problem with the drive that would cause the 12 volt power to short to ground. That would reverse the polarity on lower voltage caps. This is all a long shot though, and I'd be surprised if all that was new in the setup was the cables.