Thermaltake IGCS 12 Fans Won't Spin off Molex in Antec 1200 Case

I replaced 5 stock fans in my Antec 1200 case with Thermaltake IGCS 12 fans. The ones I hooked to my mobo work fine. The ones I hooked to the 4-pin molex lead from the PSU (Kingwin 1000W) don't spin. Other fans (the old Antec ones) spin fine off that PSU lead. Again, the Thermaltake ones that don't spin DO spin when connected to the mobo 3-pin headers--just not when connected to the 4-pin molex. And the molex lead does successfully power other fans. Any thoughts?

Molex pins are standardized:

http://en.wikipedia.org/wiki/Molex


2 middle pins are both ground (usually black)

+12V should be yellow in color

+5V should be red in color


You can check these with a standard volt meter.

Also, in case you missed this detail, some
"fan only" Molex connectors have only 2 wires
but they may not be labeled as such.

If a Molex connector has only 2 active wires,
it's definitely "fan only".


MRFS

here's a clue: I found this photo of the fan's power connectors
at the Thermaltake website:

Note that the white connector (on the right) has red and black wires
but red is the standard color for 5 Volts; however,
your fans require 12 Volts i.e. "operating voltage".

See "Spec" here:

http://www.thermaltakeusa.com/ISGC/index.html

MRFS