Question PBO won’t stay enabled

Trickle2x2

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On my MSI MEG b550 unify my PBO option will not stay enabled after my newest bios revision. Every time I go to enable it it goes back to “AUTO” after I restart. The only thing that keeps PBO enabled is if I enable MSI game boost in bios. But that just seems to lock the cpu at a 4.85mhz boost. Any idea on what’s going on?
 
On my MSI MEG b550 unify my PBO option will not stay enabled after my newest bios revision. Every time I go to enable it it goes back to “AUTO” after I restart. The only thing that keeps PBO enabled is if I enable MSI game boost in bios. But that just seems to lock the cpu at a 4.85mhz boost. Any idea on what’s going on?
Did you reset CMOS? or load Optimized Defaults at least once since updating BIOS?

I do both after an update, just to be certain I got CMOS storage properly cleared of old settings.
 
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Trickle2x2

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Did you reset CMOS? or load Optimized Defaults at least once since updating BIOS?

I do both after an update, just to be certain I got CMOS storage properly cleared of old settings.
I can try that when I get home and see if it helps, I did neither of those. It seemed my settings were already reset with the new bios revision so I didn’t bother.
 
Try to reset bios, and see if it sticks, Also go into the AMD Agesa or AMD Advanced CPU settings (Not sure what MSI labels it) and look for PBO in there, MSI just like Asus has 2 different spots for PBO, leaving the factory PBO at defaults in the AMD Advanced menu might overide the MSI PBO options, I wish I could help more, I just haven't had a AM4 MSI board yet to mess with.

Good Luck!
 
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I can try that when I get home and see if it helps, I did neither of those. It seemed my settings were already reset with the new bios revision so I didn’t bother.
I know BIOS updates are supposed to clear settings but I'm not sure they always do it completely, all locations. Hardware reset of CMOS definitely does especially when accompanied with taking out the battery.

Loading optimized defaults doesn't just reset CMOS, it actually flips certain locations to default values the mfr. considers 'optimal' for any configuration of hardware the board might be populated with. So it's also worthwhile doing it after a CMOS reset and before you start populating your customized settings.
 
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I know BIOS updates are supposed to clear settings but I'm not sure they always do it completely. Hardware reset of CMOS definitely does especially when accompanied with taking out the battery.
UEFI updates are like software updates, something changes here, something there, its not full bios image flash... once done, power cycle should trigger recovery capsule (something like cmos reset, but not exactly cmost reset..its like bios recovery mode...you know like when overclock fails it does one boot with default bios values, while your OC setting doesnt change, after reboot youre back to your overclock unless you enter setup and change things manually)
 
UEFI updates are like software updates, something changes here, something there, its not full bios image flash...
UEFI updates typically use AMI's flash update utilities. The utility I've use in the past has command line options to completely clear or partially clear CMOS locations during the update. I can only imagine why partial clearing may be useful, but it's a choice.

I also don't pretend to know what any manufacturer includes in their update command line options (I'm confident some at least use options that force checking for versioning and validity since I've run into that on some of my boards). When I consider how many people have problems after updating BIOS that clear up with a simple CMOS reset it seems a good practice to follow after every update.

I'm also aware a BIOS update might update only blocks that are changed. The better mfr's implement Rev validity checking (it only upates if the BIOS rev is in range for the current BIOS) and refuse to update if it's not. In such cases, you have to make some bridge updates to catch all previously changed blocks first. That had better be spelled out in the release notes, IMO.
 
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UEFI updates are like software updates, something changes here, something there, its not full bios image flash... once done, power cycle should trigger recovery capsule (something like cmos reset, but not exactly cmost reset..its like bios recovery mode...you know like when overclock fails it does one boot with default bios values, while your OC setting doesnt change, after reboot youre back to your overclock unless you enter setup and change things manually)

I would have thought the contrary. That the bios update is always done in the same way. I.e Over writing each block regardless. Can't find anything on what way it's done.

Given the process takes the same length of time (at least on my mobo/bios) and it literally goes along block by block. I would assume it's a complete over write. Could be wrong though.
 
I would have thought the contrary. That the bios update is always done in the same way. I.e Over writing each block regardless. Can't find anything on what way it's done.
...
I haven't read anything authoritative either...and indeed it may be one of those "internet legend" things!

BUT...it does neatly explain my experiences. For one, I've run into a BIOS rev that I couldn't update until I'd first gone back a couple revisions and updated to that one and then to the latest one. And then there's Asrock...especially their B450 boards. Their boards can have a sometimes complicated process to update across a wide revision span that involves several bridge updates.

And lastly: I've made UEFI updates using a 'hacked' BIOS that would fail the MSI validation testing. The only way to do that is use the AMI UEFI command line utility so I became familiar with the options and over-rides needed to do that. One option I found was to make block specific updates, so I know the possibility exists.

I'm not sure why the update takes the same amount of time but I suspect the utility is parsing the entire BIOS file even though it only sends the relevant blocks to the relevant address ranges of the BIOS EEPROM. And the end-of-update validation doubtless will check the entirety of BIOS contents for completeness and validity.
 

Trickle2x2

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To follow up on the situation. Resetting CMOS and loading optimized defaults seemed to do the trick. PBO stayed enabled! Thanks guys! Btw off topic kinda anyone know why my pc takes about two seconds to start it’s boot process after hitting the power button? Ever since I switched motherboards and cases it’s been like this.