. . . Are these 4 wire molex connectors? If yes the easiest is to just use splitter cables. . . . .
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If it's one of those mini connectors that has the RPM pin and PWM pin I think you can still wire them directly and not use those pins. I am not certain of the pin out though. I think it's still black and yellow, from a quick google search I did. If you leave the others I think the fan defaults to max speed.
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I woulda asked that. Splitters are the way to go, for either Molex or PWM-with-Molex.
If they're PWM fans, no sense in losing the PWM control just because you don't use the mobo ports and run Molex from PSU instead. Get the Swiftech splitter:
http://www.frozencpu.com/products/2...able_Splitter_-_SATA_Power_8W-PWM-SPL-ST.html
I think Akasa also makes one. The customer reviews suggest to me that the users don't know how to control their fans through BIOS and software, or they're nit-picky about full monitoring coverage. Since you only need the PWM pin of the CPU (or other) mobo port, you can run the yellow tach wires for additional fans to your mobo headers. If possibility you also need the ground wire -- I can't be sure. I'm pretty sure I once wired two 3-pin fans in parallel and used a second mobo port to monitor the extra fan, with only the spare tach wire connected -- nothing else. But you don't need to draw power from the mobo. Not with the Swiftech; probably not the Akasa. I've run more than a single fan from it, and it works fine.
For the 3-pin fans, yes -- you can wire the red and black in parallel. I've done it with four. But use only one fan's yellow tach wire and leave the spares out of the equation. Or try what I mentioned in the previous paragraph with available mobo ports.
I figure -- if you clean your case interior regularly, you can boot up and inspect fan operation before replacing the case side-panel. You don't have to monitor every fan, especially if you control them in groups of identical fan model.
Soldering skills: Primitive though mine are, I just taught myself. I strip a half-inch on each wire spread the thin wires of a cable in a sort of fan, tin them, and make a crude attempt to braid and then twist them together -- adding more solder last. I buy automotive self-adhesive rubber hose bandage. Electrical tape sucks. The self-adhesive stretchable rubber makes such a good insulation that you have the cut it off for removal.