Question Issue with MSI board ?

[Menopausal Manbaby]

Hello yall! I have been in the PC building hobby for some time now and this is definitely something I have never encountered before and need some help.

Some backstory ... I am building a PC for a friend. They came to me with an old XPS and wanted a MOBO, CPU, and RAM upgrade. I also suggested a new case since the mobo wouldn't fit, and new PSU. I got all the parts and threw it all together. Here is the part list

- 4000D
- MAG Z790 TOMAHAWK WIFI DDR4
- i7-13700K
- Vengeance LPX (2x16) DDR4
- CX 750M

The issue I am having is the CPU light on the board comes on and it doesnt post. I have tried every troubleshooting method under the sun, to name a few ;
- BIOS flash
- Different ram (and different configurations)
- Different PSU
-Different GPU
- No GPU
- CMOS reset
- Pulling each component one at a time
- Reseat CPU
- Check for bent pins

Thats all I can remember right now. The strange part that is troubling me is that I ended up also trying a new CPU. This ended up not having any success either. I decided to try a different board as a whole. I went with the MSI Z790 Gaming Plus WiFi and a 2x16 set of DDR5 RAM. Neither CPU worked on this new board and I tried each troubleshooting step listed above for this board as well. I am at a loss for what to do, perhaps it is some sort of user error and a silly mistake?

 

[Lutfij]

CX 750M
For the sake of relevance, is he PSU you're working with, a grey label unit or the green label unit?

How are you cooling that processor? You might want to relieve the stress on the mounting for the CPU cooler until it's just making contact with the CPU's IHS. In order to do this, you should lay the case on it's side so the cooler's weight is used to put it atop of the CPU.

Breadboard your build's innards and see if that helps. Sometimes people mistake the placement of standoffs in a case and a short prevents a POST. Yes it's happened to novices and veterans alike.