Solved! PC won't turn on after changing the processor

[AlbertoTomm]

Good morning everyone. I recently upgraded my pc with new components: a GeForce GTX 1650 graphics card (D6 VENTUS XS OC) and a new Intel I5 9400F processor. I installed the processor by disassembling the old one, but I think it is not compatible with the motherboard which is quite old, because the pc gave no signs of life. So I put the old processor back in (without putting in thermal paste because I had not bought it, because the new processor already had it pre-applied) and it started working again. I then put in the graphics card and the pc kept going. I saw on a forum that the processor compatibility could be due to the Bios not being updated, so I updated it by downloading the latest update. So I put the new processor (the I5) back in and it wasn't giving any signs of life (but I don't really care about that now). The problem is that putting the old processor back in, the computer fans turn on, however, the pc does not turn on. In addition, I think the motherboard is not among those that make the diagnostic beeps, because I have for example removed the ram and it does not make any beeps. I disassembled and reassembled the processor one more time and the pc turned on, then I waited a while and tried again and it wouldn't turn on (only the fans turned on). I tried several times to take it apart, but nothing. The processor, however, gets hot. I also tried taking the battery out and putting it back in, but nothing, and I also changed the power supply to the only other one I had (from a case).
The pc was a pre-assembled Asus and the pc components are:
- motherboard K31CD-K
- processor (old): seventh-generation i3
- graphics card (old): gtx 720
- ram 4 GB
- Storage 1TB SSD Samsung 870 Evo (which I put some time ago).
(I can't be very specific because I don't remember the specs and I can't see them because the pc doesn't work)
The pc is the same, but with some differences in hardware, as this one: https://www.esseshop.it/pc-asus-k31cdkit013t-p-82556.html
I premise that I am not an expert in pc assembly.
Thank you very much.
Some pictures (old processor):
https://ibb.co/F80vP4c
https://ibb.co/NSjCMcW
https://ibb.co/mvJzFYK

 

[Shmee]

Hello, first, a 9400F will not work in your motherboard, even with a BIOS update. The reason is, though 6th through 9th gen use the same socket essentially, 6th and 7th gen use chipsets not compatible with 8th and 9th gen CPUs, and vice versa. Your motherboard cannot upgrade past 7th gen, though you could potentially put a 7th gen i7 in that board, assuming you can get it working again.

As for the current problem, where the system will not boot with the old CPU, there are a few things that are possible. It is possible that the board was damaged, such as pins bent in the CPU socket, and now the board is dead. Hopefully not the case.

Some things you can try: make sure the connections are properly connected, such as power connections, fan, and make sure the cooler is installed correctly and that there is the right amount of thermal paste. Make sure your RAM isn't loose, and is inserted properly.

Also, assuming you have one of your graphics cards installed, make sure your monitor is connected to an output on the graphics card, and not the integrated graphics on the motherboard.

 

[AlbertoTomm]

‎As for the current problem, where the system will not boot with the old CPU, there are a few things that are possible. It is possible that the board was damaged, such as pins bent in the CPU socket, and now the board is dead. Hopefully not the case.

I went to check and I think one pin is bent. Is it possible to put it back in the correct position with a small plier? (Instead of throwing out the motherboard right away).

 

[Shmee]

It is possible to very carefully straighten a bent pin, you could give it a try. I wouldn't use a pliers though, but rather something like the tip of a sharp knife, to carefully try to straighten it. No guarantees it will work, but if the board isn't functioning at all right now, it is could be worth a try.

 

[DAPUNISHER]

I have the vid set to start when Greg addresses the bent pins and straightens them. It should give you the info you need to do it.

 

[AlbertoTomm]

thanks