Bios Unlocks Athlon 5370 CPU and then Forgets?

Question

I have a new Biostar AM1MH mATX motherboard that I've installed an Athlon 5370 into. This CPU is a locked CPU - however, on first boot, and whenever I clear CMOS, the BIOS clearly shows that we can overclock this CPU from its stock 2.2ghz up to (theoretically) 3.6ghz, as well as overvolt it accordingly.

However, on the next boot (after saving settings), the BIOS clearly shows that we can only go up to the stock clock:

What's crazier about all this is that if I do set things way too high (I tried 3ghz with AHCI on, for example), the computer fails to POST just like it would with an extremely unstable OC, and I'm forced to clear CMOS. But if the system doesn't become unstable, it simply reverts to 2.2ghz on the next boot.

Now I did not buy this motherboard with the expectation of OCing on it, so don't bother telling me it can't. I "know" that already. The mystery I'd like to solve here is why does the BIOS behave this way, and does it provide any hints for potentially modding this (AMI) BIOS to unlock CPU overclocking?

Answer 1

It turns out I have a partial answer to this question. Working with vendor-supplied tools and the frequent user DeathBringer over at www.bios-mods.com, I was able to use the custom-built UEFI Tool and IFR Extractor, along with Notepad++, to get a modified UEFI environment which unlocks these menus.

Unfortunately it is a partial answer because:

• It doesn't answer why Biostar's stock UEFI shows you these options on first boot
• It doesn't actually succeed in overclocking the system, only exposing the options, so we still don't know if we're going down the right path or not.

I don't think I can in good conscience award myself the bounty or even the answer check on this one, because we are still pretty far from the mark, but research and development continues and we will probably eventually crack this nut (or prove that it cannot be cracked). Interested parties should follow up on the forum.