Question PSU died out of nowhere. Still get error codes after swapping out GPU

[Flying_Davis]

I recently upgraded my PC (specs below). After about a week of use my PSU breaks. My initial theory is that the 3090 had a power spike and blew my PSU. However, after getting a replacement PSU the motherboard still displays a VGA error code even after putting in my old GTX1060 into the PC. My friends have the theory that the 750W PSU was definitely not enough for a 3090 (even though that's the PSU Nvidia recommends) and the power spike that blew my PSU also damaged the motherboard and that's why I still get the VGA error beep code. The weird part is that the computer works perfectly fine even with the error codes. Should I try to get a replacement motherboard to test if the motherboard is broken? Maybe there are any others problems that I don't know about.

Specs:
AMD Ryzen 7 5800X
RTX 3090 Founder's Edition
Corsair CX750M
ASUS ROG STRIX B550-F GAMING
Corsair Vengeance DDR4 2666 Mhz 16gb (2x8gb)

 

[Vic 40]

Is the CX 750M the new psu? Not something you should use with a 3090, if possible return it and get something better.

Did you try a clear cmos?

 

[Flying_Davis]

Ok I understand that my PSU isn't powerful enough. However, I want to check is there is anything wrong with my motherboard. I cleared cmos and I got the same error code but this time my computer won't boot. I am using a 1060 currently instead of the 3090

 

[Flying_Davis]

Is the CX 750M the new psu? Not something you should use with a 3090, if possible return it and get something better.

Did you try a clear cmos?

I cleared CMOS. Now the PC won't boot with my 1060 and still has the same error code. I tried to boot the PC up with my 3090 (just to check and not actually use, as to not damage PSU) and the PC boots up no problem without any error codes.

 

[Vic 40]

Ok I understand that my PSU isn't powerful enough.

It's not just about the 750watts , it's about quality of he build and more impoirtantly platform which i sued in this case. This psu's platform is called "double forward topology " which is and old design which doesn't work well with for instance these newer gpu's.

However, I want to check is there is anything wrong with my motherboard. I cleared cmos and I got the same error code but this time my computer won't boot. I am using a 1060 currently instead of the 3090

So with the 3090 it now boots fine? Still don't recommend using that gpu with the current psu under stressfull circumstances, but at least your able to do light stuff like maybe update bios. What bios does the motherboard run? Can use "dxdiag" (rightclick start button->run) to see.
Why the 1060 doesn't work i cannot say.