Question PC Not power up

[rk496928]

I have Dell optiplex 3040 PC with 8 pin power supply. one day PC not turn on, then i replace the PSU. But still PC not turn on. this PSU have a black color button near power connection, when i press that button CPU fan spin and LED is on but nothing else. Please anyone help me.

 

[Ralston18]

What make, model, wattage, age, and condition for both PSU's?

No beeps from the motherboard?

No screen popup's?

Have you tried replacing the motherboard's CMOS battery?

https://www.dell.com/support/articl...battery-on-your-dell-desktop-computer?lang=en