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Considering BIOS Downgrade (A10 Unlocked -> A05 Unlocked)

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Hi all. I'm considering downgrading (blind-flash method, verified it works on this system before) my M17x R4's system BIOS from A10 Unlocked to A05 Unlocked. Reason being the idle clock for the Intel iGPU - I liked the behavior much better in A05 and earlier. I was able to idle at 350MHz(qm chip)/400MHz(xm chip) instead of the advertied 650MHz, which results in significant idle power savings. The new BIOS does still allow for this, but only if the system is exposed to AC power (yes, adapter is original.) The problem is if I have to restart my system for any reason while on battery power, I get stuck with 650MHz iGPU clock and a 25% greater overall idle power draw until I can plug in. I've documented this behavior further in a previous post, but for this question let's not focus on the reason I want to downgrade - unless you know another way I can force the behavior I want.

What I want to ask is this: Other than the CPU microcode update which does not apply to my current ES CPU, the new Windows 8-related features, and the slightly faster POST, are we aware of any other meaningful differences between the two BIOSes? Differences in system performance? I did notice a slight improvement with A10 over A05 on my previous CPU but I attributed that to the microcode update, which no longer applies to my current CPU. I've yet to run A05 on my current ES CPU.

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Note: Tried and Reverted.

No differences seen in general system performance (since CPU microcode update does not apply to my system) BUT Intel DPTF does not seem to function correctly with A05 BIOS installed. It's still present in the BIOS but it no longer interacts correctly with the Windows environment. This would not affect users of unmodified M17x's but I have installed the DPTF driver from the M18x R2 and in combination with my 3920xm CPU and some configuring in BIOS, it allows me to set custom changeable TDP's and max non-turbo speeds as part of my Windows power profiles - and to drop the CPU into an ultra-low power state (800MHz) if desired. Tried re-installing DPTF driver after downgrading to A05 but this functionality, despite being configured identically in BIOS, was lost in Windows when running A05.

You gotta admit this changeable TDP thing is pretty cool so I'm going back to A10 for now:


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