American Megatrends Inc. BIOS Update

Hello,
I have a compatibility issue with my motherboard Asus M2M68-AM PLUS and my AMD Athlon 64 X2 6000+ @ 3000 MHz processor. I have read on several computer sites that updating my BIOS might solve this problem, but that it is very risky, so it should be done only if necessary. I do have such a necessity; my PC experiences a sort of regular lag (every 1 or 2 minutes and lasting 15 to 30 seconds generally). This lag causes my games to crash except for two (Dofus and Wakfu, that is...). I would like some help to update my BIOS (American Megatrends Inc., version 1802). I'm not a novice, but with all these warnings, I would like to be sure of my steps (you understand me). I couldn't find specific BIOS updates but I found a lot of small updates on the Asus site: https://www.asus.com/fr/#download Question: Are these the right updates? I downloaded the latest one (the one before is version 1802), should I leave the folder on my SD card or just the .ROM file?

Thank you for your responses, and I'm all ears for any missing information!

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