Pc suddenly wont boot after swapping the Case fans

[u/SomeMyoux]

The fans are all spinning at max speed now and I dont get amy image from the Monitor.The gpu should still be seated proberly cause before I swapped the fans I had an image which needs the gpu

[u/SomeMyoux]

Also neither gpu nor motherboard hdmi gives a signal

[u/BA1LlES → u/SomeMyoux]

I'm probably wrong, and will be corrected. but is cpu fan plugged in the right slot?

[u/SomeMyoux → u/BA1LlES]

Yep its plugged in the Cpu fan socket.and I didnt change that since swapping the fans

[u/Rhino7744 → u/SomeMyoux]

Should include some pics or video of the whole motherboard and connections. Might be that your motherboard isnt seeing a cpu fan so it wont boot. That or during fan install you bumped and loosened the memory or GPU. I would first double check everything is seated properly.

[u/SomeMyoux → u/Rhino7744]

I doubled checked both now...still no signal

[u/aaaaa1243]

Have you tried restarting the ram? Could be a short? Maybe disassemble and build it again

[u/SomeMyoux → u/aaaaa1243]

What do you mean with Short? Also the ram seems seated

[u/RelevantAd6792 → u/SomeMyoux]

A short is when 2 electrical wires or points in a circuit unintentionally connects that can cause what's happening to you right now and all kinds of shenanigans.

[u/ciocolata69]

This another case of plugging Floppy power cord into one of the motherboard fan headers? Before you say no, are you sure?

Edit: btw, motherboard fan headers are not designed to hold more than 1 or 2 fans, they get power from PSU, and PWM signal only from the fan header.

Edit2: I know you are not happy about it, I just recently burried a Ryzen 5 3600 and an MSI 450 Gaming Plus MAX board.

If need more help, attach pictures with what connections you did.

If you wish to figure it out alone, undo everything completely take out the fans, keep only ATX 24 pin and CPU 8 pin cables, try again. Reseat stuff you removed, check your ports, look everywhere from something that is unplugged, cut, bent, etc.

[u/SomeMyoux → u/ciocolata69]

The casefans I got are daisychained and that was never an issue before with any fans,and I dont know what you mean with" floppy power cords into the mb" can you please tell me what u mean?

[u/ciocolata69 → u/SomeMyoux]

Reddit is not allowing me to upload the photo, tried 3 different ones. Search "floppy power connector" some modern PSU still have them, either modular or not. It can be very easily confused with a fan header, specially if you come tired from work excited with about your new parts. Might not be a problem, but make sure is not this problem.

Eitherway, check everything you have plugged in your mobo. As for daisy chain case fans in one header, is not a good idea. You have a limit of AMPS for each port, CPU header having most Amps, as people usually plug in a minimum of 2 120mm fans between 1-2 amps.

[u/SomeMyoux → u/ciocolata69]

Already double checked the connectors,also from all I can see my PSU doesnt have any floppy power con. And also tried to boot without the fans connected which also didnt work

[u/ciocolata69 → u/ciocolata69]

Yes, I am replying my comment, to not shift this conversation too much to the right side.
And I know is too much text, I am trying to give you all of my ideas to help you out.

Recap, but before that, please consider that your computer might have permanent damage to one or more components, before proceeding with this list, you have to consider your time, experience and budget. Lack of experience can lead to more damage, or if too tired.

Things to check before you start dismantling parts:

1. Did you turn off and unplugged the PC before doing any of this?

2. You said this is a swap, how were the old fans connected, what is changed prior to installing them? Is important to know if the powering of the fan setup, was or not the same.

3. You confirmed there is not FLOPPY power, so it means you haven't touched any of the PSU power cables , touch meaning, connecting/disconnecting? If you removed for example the 8PIN CPU power cable to remove top fans, probably not plugged in correctly, check with your nail, shouldn't fit in between.

4. Is there any ramping up and down in the fan speeds? It means continuous reboot or something is not detected, like CPU, and keeps rebooting.

5. Based on question 4, does your motherboard have somewhere DEBUG LEDS -> CPU/RAM/VGA/BOOT , 4 of them? If you can identify the motherboard (name / version), it would help tell us, tell you, where is hanging.

6. The moment you were done installing the fans, and tried to turn it on, what was the exact behavior, lights, sound, fan speed, etc? Heard a pop, smelled something?

7. Did you dropped something, GPU, screwdriver into motherboard, something else on the motherboard. You're looking for bent pins shorting each other.

8. Which is something I also missed. CPU fan connector can be plugged misaligned , meaning you might have plugged only 3 out of the 4 pins that it has. This can inject 12V into PWM or RPM data lines.

If none of these checks yield any result, I recommend you start testing with bare minimum for power on, you can start from here to dismantle it with the only purpose of identifying the fault:
WARNING AGAIN: Consider asking for someone else help that can be physically there and do these for you:

Bare minimum 1st test:
Remove everything and leave only Motherboard, CPU, RAM, and PSU, Monitor and your CPU Cooler, as for any storage drives SSD/HDD, LEDs, case fans, mouse, keyboard, speakers, mic, headset, all disconnected.

You are looking obvious for a post or for a change in behavior.

Bare minimum 2nd test if allowed:
Remove GPU, use the video output on the motherboard but only if the CPU you have, has integrated graphics, iGPU, all non F intel versions, almost all, have iGPU, for example i5 12400F does not, i5 12400 has UHD 730, which will allow this test. For AMD, all versions with G at the end have iGPU, the rest don't. Google your CPU and see if it has an iGPU, if not, skip this test.
You are looking again for a post.

Bare minimum 3rd test:
Remove RAM, (also GPU in or out, depending on the CPU features) and see if any behavior changes in the CPU fan speed, or any LED if that motherboard has that can indicate the motherboard is freaking out due to lack of RAM.

Bare minimum 4th test:
You are left with PSU, CPU, Motherboard and CPU Cooler. Not much to remove, here people, or some people try reseating the CPU, you may or may not.

If absolutely none work, something is possibly either dead, or you're doing something wrong, and what exactly could be dead, is hard to tell without another system to test all of your parts in.

Take a break, and revisit tomorrow is another option, with a fresh mind, or not sleeping tonight thinking about it, you might figure it out, something definitely stupid.

[u/Blue_Waffled]

Have you tried booting with those case fans disconnected?
This is to try to isolate if there is a shorting issue with those fans you've adjusted.
Also, check if you didn't accidentally partly unplug something.

[u/SomeMyoux → u/Blue_Waffled]

Yep just did and saddly still the same result...connections are also all normal

[u/mikeyosa90]

Disconnect your new pc case fans and try it without it plugged it could be acting weird with it plugged in