Can someone explain to me CPU cooling and MOBO conections to the fan?

Righty,

CPU is a pentium D 2.8
MOBO is ASrock ConRoe1333-D667 R1.0, this one http://www.asrock.com/mb/overview.asp?Model=ConRoe1333-D667%20R1.0&s=n
The fan is Thermaltake A4013 TR2 M13 P4 LGA-775 CPU Cooler, and is quite frankly rubbish (both noisy and not too cool).

The MOBO has a 4-pin connector, the fan is a 3 pin.

In the BIOS I set the fan target speed to slow and target tempreature to max (65deg c). But this has had no effect (it still sounds like a small concorde on take off, just the same as before).

What am I doing wrong? I read that the fourth wire is used by some fans to regulate speed, but plenty of other coolers claim to be variable speed without the fourth wire, so why isnt this one slowing down? I presume the 3rd wire is an RPM signal (currently 2700rpm), so why isnt the MOBO droping the fan speed via PWM?

I'm a bit wary of going out and buying a £30/$60 cooler, pluging it in and it spinning merrily away making just as much noise rather than spinning nice and slowly.

so my questions are.........
why isnt my fan slowing down?
what does the 4th fan wire do?
will a better cooler slow down/speed up in this setup?
should i just invest in a passive cooler and a case fan as im not overclocking and the PSU fan is drawing air over the CPU anyway?

 

This is the only question I can answer with any certainty.... the 4th wire (AFAIK) is used to monitor and control fan speed. This would explain the problems you're having. Grab yourself a different heatsink/fan unit for the CPU with 4 leads and it should be OK. ThermalTake tends to have higher priced stuff, and I have no idea why. I think most of their products are trash also.....
good luck!

 

cheers, wikipedia'd it and found that the first three are +ve, 0v and rpm monitir, the fourth is a PWM controller, not sure why that cant be done in the +ve wire but someone probably does.

I'm looking at fans with automaticaly adjustable speed and are quiet at full pelt (in case the mobo doesn't controll via the first 3 pins and it reverts to this).