Topic: Overclocking Phenom II x6 CPU's with PhenomMsrTweaker
Hardware specific:
CPU = Phenom II x6 1090T
Motherboard = MSI 890FXA-GD70
Software Tools:
PhenomMsrTweaker
CPU-Z
Prime95
IntelBurnTest
Purpose: When you can't disable the hardware Cool 'n' Quiet (CnQ) on the Phenom II Hexacore CPU's, and you can't overclock into Windows at 4.0GHz - 4.2GHz stable (I personally could never get into Windows stable at 4.2GHz with the MSI 890FXA-GD70 and ASUS M4A87TD/USB3 motherboards - I've even had trouble getting into 4.0GHz stable with the MSI 890FXA-GD70 at times). When you can't disable CnQ, you'll notice throttling occurring (Core Speed fluctuates, along with Core Voltages). I believe this "throttling" is what's causing instability when logging into Windows at high overclocks and voltages on some AM3 motherboards.
Step 1: (Note - Motherboard BIOS's will be different.)
Enter into your BIOS and configure your settings.
AMD Cool 'n' Quiet (Disabled)
C1E Support (Disabled)
Set your default clock speeds (FSB to 200)
Set your default CPU multiplier (x16)
CPU-NB Ratio (x10)

Step 2:
Set your FSB/DRAM ratio (1:4) which ends up being 1600MHz
Set your HT Link Speed (x10)

Step 3:
Set your CPU Voltage to 1.3v
Set your CPU-NB Voltage to 1.15v
Set your DRAM Voltage to 1.65v
Set your HT Link Voltage to 1.3v
Spread Spectrum (Disabled)

Step 4:
Enter your Advanced DRAM Configuration...

Step 5:
Set your rated DRAM Timings (9-9-9-24-1T)


Step 6:
When you log into Windows, you should be stable since you're logging in with default voltages, multiplier, FSB, and RAM timings.
Install and launch PhenomMsrTweaker, you'll notice each P0/P1/P2/P3/P4 tab will have different Core multis, CPU VID, and NB VID. P0 being the maximum performance state, and P3 being the most power-saving state, and P4 I'm not too sure what that state is. What you see with the asterik (*) is what setting the CPU state is currently at. Notice my Core Speed is at 1.6GHz when it should be 3.2GHz by default. That's because hardware CnQ isn't being disabled inside the CPU, even though the BIOS settings we changed earlier was supposed to disable it.

Step 7:
When you change each Core multis, CPU VID, and NB VID in each P0/P1/P2/P3/P4 tab to be identical, that means each state will always be the same no matter what.

Step 8:
Perform a full round of Prime95 Blend tests to ensure stability, and 5 runs of IntelBurnTest to ensure throttling doesn't occur. Keep an eye on what your Core Voltage spikes up to in CPU-Z, and monitor your core temps. Notice the GFlops difference between the default CnQ and the changed CnQ stable at 4.0GHz.
Important! Some motherboards with PhenomMsrTweaker react more like an Offset voltage than Manual voltage. So if you're at CPU VID 1.45v and you're hitting 1.52v or higher (even seeing 1.6v), then it's acting like Offset voltage. You'll need to tweak around a bit more so that the voltages doesn't spike that high. If this is what's occuring, start from CPU VID 1.3v and work your way up or down so that your voltages at 4.0GHz is around 1.46v (min) - 1.51v (max) through CPU-Z..

Step 9:
Once it's stable, you can make sure your overclocks are always applied at start-up by going into PhenomMsrTweaker Services to Update and mark the checkbox to make custom P-state settings permanent, and hitting Apply.

Conclusion:
With PhenomMsrTweaker, we managed to "disable" the hardware CnQ that the BIOS couldn't turn off. We essentially set each CPU state to be the same, so whenever there's a difference in CPU usage, if the CPU state changes, it won't matter because they're now all the same. We didn't actually "disable" hardware CnQ, we just tricked it into keeping the same settings for each CPU state. What's cool is that you can also set a custom CnQ for when your CPU usage is idle to low, it's at lower voltages and frequencies so you're not consuming as much power. We can go over that in another Tutorial.
