do9105

So to make a long story short I wanted to replace my CPU fan. I don't know what came over me to do so.. But I "did it". Anyways heres the problem: I went to best buy to buy a new cpu fan and i guess you cant buy a fan under 80mm there. So I ended up buying a $30 rocketfish cpu fan/ heatsink combo. It's definitelly better than my stock fan and heatsink. When I went home and installed it I went to turn the computer on and for about 5 seconds the fan will spin and then it will stop and every few seconds it will twitch a little bit acting like its trying to spin.. Then I will get an error message that says CPU fan failing computer turning off.. or something to that effect. So I found a little work around if I manually spun the fan with my finger while booting up it would work. I ended up just laying an old fan on top of the heatsink while plugged in and thats been working pretty good. But the fan is supposed to have High, Medium, and Low settings. But when this fan is set to medium and low it does the same thing as the first fan. But when I turn it on High the fan only spins at the speed it should on low.. I have no idea what the problem is but I'd like to fix it.

One thing about the first fan is that it has 4 pins.. the red, black, white, and blue one. I've read about what the blue one is for, but I don't have a plugin on my motherboard for the 4th pin (the blue one). So I just plugged it in so the red white and blue were plugged in.

Any ideas? I realize that was a lot of reading.. So I'm sure something in there isn't going to make sense. Just let me know and I'll clarify.. haha. Thanks for your helppp...