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Case fans connected to mobo not turning on

I have an MSI B450 AMD Motherboard Gaming Plus Max and I use 1 built-in case fan for the back and 2 fans with white LEDs I bought for the front, all 120mm. The back one has a 3 pin slot and the other 2 have a 4 pin slot each. I have them all connected to the motherboard, the front ones on sys_fan 1 and 2, the back one on sys_fan 3. Keep in mind, I don't have a graphics card yet (and missed out on the RTX 3070), but everything else in the pc runs, such as LEDs on the mobo, but nothing about the fans work.
Can anyone help me? Feel free to ask questions that will help resolve this, thanks

Edit: I haven't installed windows yet or updated BIOS, but idk if I need to, and my power supply is 650W and 80 plus Bronze certified.

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The first thought I have is The difference between 3 pin and 4 pin is pwm.  3pin fans have no pwm sensor wire. It is reasonable that the 3 pin back fan doses to spin when attached to the sys fan. The front 4 pin fans attached to non sys fan motherboard ports should work though unless their fan curve is being controlled in such a way as whatever they are measuring (which may be different both from each other and from sys fan) isn’t getting hot enough to tell them to spin.  There could also be a hardware issue with the motherboard or the fans, but I personally would make sure the fans are comparing to the right sensor and the fan curves make sense before even looking at hardware possibilities.

Life is like a bowl of chocolates: there are all these little crinkly paper cups everywhere.

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There's not much we can help you with here if you can't get a video signal. I'm assuming you're using Ryzen X model and not an APU? 
If you are running a Zen 2, you may in fact need a BIOS update. But again, it would very much help to have some video output. You should be able to find a GT710 or something similarly wimpy for ~10USD on eBay or the likes, just to get some video to see what's happening. 

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2 hours ago, thermalgoop said:

There's not much we can help you with here if you can't get a video signal. I'm assuming you're using Ryzen X model and not an APU? 
If you are running a Zen 2, you may in fact need a BIOS update. But again, it would very much help to have some video output. You should be able to find a GT710 or something similarly wimpy for ~10USD on eBay or the likes, just to get some video to see what's happening. 

I am using a Ryzen 7 3700X, and my graphics card comes on Saturday

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Well, let us know what happens when that's all hooked up. 👍 Might have some better advice if things are still awry then.

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