- Joined
- Dec 19, 2012
With the new Ryzen platform as soon as you modify the multiplier or FSB all power saving features are disabled, so in Windows your system will run at full speed regardless of OS power settings. Most people who are running their system as a daily driver still like to overclock it to get some additional (free) performance. It just seems that's not going to happen with the Ryzen. Or is it? If you're using an ASUS Crosshair VI Hero, they have included an option that allows you to alter the P-states. Essentially, this tells the CPU that it has a new top speed without disabling all the power savings that are built into it. This process isn't really plug and play without a bit of background work initially so you'll want to have a couple things handy before you start.
You'll need some paper and a pen/pencil for chicken scratching.
A calculator and a HEX<>Decimal converter. I have both of these on my Cell thanks to a free app called Hex plus from google play.
So let's dig in. First thing I want to get out of the way is, this is just a guide and you are altering the basic operation of your CPU and I'm not responsible for any damage you may incur. Use at your own risk. It has been brought to my attention that using P-state OC and having a failed boot can cause overvoltage upon reboot caused from the XFR on thw "X" models. To stop this from happening YOU MUST DISABLE TURBO/CPB
First navigate to the Advanced section in your BIOS and select the AMD CBS > ZEN Options > Custom Core P-ststes > Accept > Here's the P-state screen.
We're going to start with P-State 0 so open that one by selecting custom in the drop down.
As you can see it shows the current max speed all cores which for my R7 1700x is 3400 without XFR, You should see this really cool warning at the bottom which basically says if you break something then you're warranty is void. The main points of interest here are Pstate0 FID and DID. FID is the number you'll want to change to alter the P0 state of your CPU. I have found it's best to leave the DID as it is. I have also tried changing the VID but haven't been successful yet. Seems any time I change it I get a top speed of 3000 in Windows. We'll take care of the voltage with an offset to the V_Core in the Extreme Tweaker section.
OK this si the formula we'll be working with for altering the Pstates going forward.
CPU Ratio = 0.25*FID/(DID*0.125)
Fist thing I need to point out is that the FID and DID you see in the BIOS page are hexidecimal numbers and need to be converted prior to plugging them into the formula. I'll go through with the stock values as an example first.
CPU Ratio = 0.25*FID/(DID*0.125)
CPU Ratio = 0.25*88/(8*0.125) converting the values from hex to decimal we get
CPU Ratio = 0.25*136/(8*0.125) as you see 8 is the same in both
CPU Ratio = 34/1 or 34 for the multiplier.
OK so to get a 40x multiplier we need to solve the equation for FID
CPU Ratio = 0.25*FID/(DID*0.125)
40 = 0.25*FID/(8*0.125)
40 = 0.25*FID/1
FID = 40/0.25
FID = 160 converted to Hex is A0
There is also a formula for finding your VID
Core Voltage = 1.55-0.00625*VID
Running through it with the stock values returns 1.35v which is what the BIOS says it is just above 1350000 uV or 1.35v. I know from testing I require ~ 1.4v for 4.0 GHz. This means I'll need a 0.05v+ offset added to the CPU Core voltage which I input on the tweaker page of the BIOS
Ok , we plug this new value into the BIOS page like so, with the offset added to the V_Core, it should boot straight to windows.
And it does, after Windows starts I open CPUz and voila 4.0 GHz
OK, got that to work now I set the power plan in Windows to Balanced but I'm getting a speed of 2.2GHz now which to me isn't really slow enough for a low power state
So back into the BIOS I go, this time we'll be altering the Pstate2 section as you can see in the pic below I also have Pstate1 open showing 3.0 GHZ which is fine so no alteration needed.
So same as above we'll apply the formula and my goal is 1500 so a multiplier of 15x. You'll also notice the DID is a different value this time which I'm not going to change.
CPU Ratio = 0.25*FID/(DID*0.125) DID = C C= 12 in decimal
15= 0.25*FID/(12*0.125)
15= 0.25*FID/1.5
15*1.5= 0.25*FID
FID= (15*1.5)/0.25
FID= 90 which is 5A in Hexidecimal.
Ok now upon rebbot into Windows with the balanced power plan I have 4.0GHz top speed and 1.5GHz at idle. Seemed like it took Windows a bit to catch up to the change but with ~ 30 seconds the speed finally dropped down as well as the voltage as you can see here
You'll need some paper and a pen/pencil for chicken scratching.
A calculator and a HEX<>Decimal converter. I have both of these on my Cell thanks to a free app called Hex plus from google play.
So let's dig in. First thing I want to get out of the way is, this is just a guide and you are altering the basic operation of your CPU and I'm not responsible for any damage you may incur. Use at your own risk. It has been brought to my attention that using P-state OC and having a failed boot can cause overvoltage upon reboot caused from the XFR on thw "X" models. To stop this from happening YOU MUST DISABLE TURBO/CPB
First navigate to the Advanced section in your BIOS and select the AMD CBS > ZEN Options > Custom Core P-ststes > Accept > Here's the P-state screen.
We're going to start with P-State 0 so open that one by selecting custom in the drop down.
As you can see it shows the current max speed all cores which for my R7 1700x is 3400 without XFR, You should see this really cool warning at the bottom which basically says if you break something then you're warranty is void. The main points of interest here are Pstate0 FID and DID. FID is the number you'll want to change to alter the P0 state of your CPU. I have found it's best to leave the DID as it is. I have also tried changing the VID but haven't been successful yet. Seems any time I change it I get a top speed of 3000 in Windows. We'll take care of the voltage with an offset to the V_Core in the Extreme Tweaker section.
OK this si the formula we'll be working with for altering the Pstates going forward.
CPU Ratio = 0.25*FID/(DID*0.125)
Fist thing I need to point out is that the FID and DID you see in the BIOS page are hexidecimal numbers and need to be converted prior to plugging them into the formula. I'll go through with the stock values as an example first.
CPU Ratio = 0.25*FID/(DID*0.125)
CPU Ratio = 0.25*88/(8*0.125) converting the values from hex to decimal we get
CPU Ratio = 0.25*136/(8*0.125) as you see 8 is the same in both
CPU Ratio = 34/1 or 34 for the multiplier.
OK so to get a 40x multiplier we need to solve the equation for FID
CPU Ratio = 0.25*FID/(DID*0.125)
40 = 0.25*FID/(8*0.125)
40 = 0.25*FID/1
FID = 40/0.25
FID = 160 converted to Hex is A0
There is also a formula for finding your VID
Core Voltage = 1.55-0.00625*VID
Running through it with the stock values returns 1.35v which is what the BIOS says it is just above 1350000 uV or 1.35v. I know from testing I require ~ 1.4v for 4.0 GHz. This means I'll need a 0.05v+ offset added to the CPU Core voltage which I input on the tweaker page of the BIOS
Ok , we plug this new value into the BIOS page like so, with the offset added to the V_Core, it should boot straight to windows.
And it does, after Windows starts I open CPUz and voila 4.0 GHz
OK, got that to work now I set the power plan in Windows to Balanced but I'm getting a speed of 2.2GHz now which to me isn't really slow enough for a low power state
So back into the BIOS I go, this time we'll be altering the Pstate2 section as you can see in the pic below I also have Pstate1 open showing 3.0 GHZ which is fine so no alteration needed.
So same as above we'll apply the formula and my goal is 1500 so a multiplier of 15x. You'll also notice the DID is a different value this time which I'm not going to change.
CPU Ratio = 0.25*FID/(DID*0.125) DID = C C= 12 in decimal
15= 0.25*FID/(12*0.125)
15= 0.25*FID/1.5
15*1.5= 0.25*FID
FID= (15*1.5)/0.25
FID= 90 which is 5A in Hexidecimal.
Ok now upon rebbot into Windows with the balanced power plan I have 4.0GHz top speed and 1.5GHz at idle. Seemed like it took Windows a bit to catch up to the change but with ~ 30 seconds the speed finally dropped down as well as the voltage as you can see here
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