New AMD CPU, PC freezes under load

Question

But now to the topic:

I've bought a new CPU, the AMD FX-9590 (AM3+).

And I'm using it on my Asus M5A99X EVO R2.0 Motherboard.

Everything works great, I have enough power, enough cooling, great airflow, newest drivers, newest BIOS, freshly (after new CPU) installed Windows 10 and so on.

But if I give my CPU some work to do (prime95), the PC freezes after a random amount of time.

I've checked the motherboard manual and searched for the list of supported CPU's. As described here, my new CPU is not listed. There is a new version of this Board, the Asus M5A99FX. There, my new CPU is listed.

My questions are:

1. Is it possible that my described problem (the freezing) is caused by a non supported CPU of an old(er) motherboard?

2. And is it required to only use CPUs that are listed as supported, even if the socket (AM3+) is the same?

Answer 1

Is it possible that my described problem (the freezing) is caused by a non supported CPU of an old(er) Motherboard?

Yes. The BIOS may not know how to correctly configure the CPU. The VRM may not be able to provide it enough power. Lots of things can go wrong.

And is it required to only use CPU's that are listed as supported, even if the socket (am3+) is the same?

It's not literally required. But it's dangerous unless you have very good reasons to believe that the particular combination you are using will work. At a minimum, the combination will not have been tested by the motherboard manufacturer or, worse, tested and failed.