You are now into PC repair. As you omitted PC details all you may get is to replace the motherboard too.
I can't check the old MB for what may be different or the new PSU for issues like a quad rail +12V.
Bob
I just got a new graphics card, and got a new PSU for it. So I installed the new components, and the computer started beeping. I switched the graphics card back, and it kept doing it. But when I switched back to the old PSU, it worked fine. This is NOT a RAM error, to be clear, do not tell me it is RAM. My computer is older, so I'm not sure if that is the problem, but all of the cables are identical between the new and old PSU.

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