Odd issue with pc fans not staying on

Hey there Tek syndicate forum. Okay so I've resently bought a noctua NH-D14 and two NF-F12's and one NF-A15 to replace the to included fans and to add a third. Well here is the problem, I have a totall of 6 case fans and 2 on the D14 (besides the third fan that hasn't been added to the D14 yet) and for some reason they all turn on on boot but then one turns off after a few seconds of booting into windows. I tried plugging said fan into a different plug and it still does it. I even tried plugging in the third fan that isn't installed yet on the D14 and it does the same thing. I'm not really sure why it's doing this and it's really bugging me. It seems to be starting to do it on some other fans as well besides the cpu fan header. Oh but if I plug in a fan to the cpu opt header it does it too. Oh and the system worked no problem the first time I booted it up after installing both the D14 and the added fans. Oh and I plugged all the fans right into the mobo fan headers using the included noctua "y" splitters and even tried plugging some of them into the built in fan controler on my case and only a few of them right into the mobo. If anyone has any idea what is going on, please let me know. Thanks in advance.

Have you gone into the BIOS to enable/disable the fans?

Do they run off a molex cable? If they dont then they are toast. If they do then it something with the board and or BIOS.

I do not have them plugged into a molex but even the fans that are running right now, that being the two fans that are attached to the cpu header with a y-splitter will do the same if I plug them into a diferent header. I think it actually may just be the BIOS. Do you think that maybe they aren't getting enough power? Oh and as a side note, I was able to plug them into a diferent computer and they work no problem but when they are plugged into mine they just sit there and twitch :/.

why you make another thread? anyways, why cant you just connect those fans to your 12v rail? seems like maybe your  board doesnt have enough power when you split the connection.

I made a new one cause the other one stopped showing up. Oh and I have no idea what a 12v rail is lol. I now only have three fans plugged in and it still doesn't work. Plus if they are running on boot but stop, how is it that the mobo doesn't have enough power? Plus if the two noctua fans are plugged into splitter and are plugged into the cpu fan header, how come they don't do the same thing?