Hi, I'm David, an Independent Advisor, here to help you.
Is this PC assembled by a manufacturer, or is it customized?
"To be filled by o.e.m." is a registry entry that comes from the BIOS and usually indicates that you are using a motherboard purchased directly from the manufacturer.
Some manufacturers do not always fill in the number correctly.
I see that your motherboard was manufactured by "MSI", and the model is "B450 GAMING PRO CARBON AC".
Try to get the serial number as shown in the article below.
https://www.howtogeek.com/294712/how-to-find-yo...
You can also retrieve the motherboard serial number, as shown in the article below.
https://www.howtogeek.com/208420/how-to-check-y...
I hope this helps. Feel free to ask back any questions.
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