Currently a bunch of the ASUS 8-Series boards have a fun issue with LLC where it creates a huge VDroop.
As of now these motherboards are listed as to have the problem:
M4A89GTD-Pro (USB3 included)
M4A89TD-Pro
CH IV
Whats going on here? Here is the plain and simple fact of whats happening. When LLC is enabled, the correct voltage is applied to the CPUv but when the CPU is in need of more voltage, it is usually limited by the amount given. LLC allows the CPU to use more voltage, creating a much more stable environment. When LLC is turned off, a VDroop is applied to the CPUv. This drop in voltage can be anywere from .05v to .1v.
The VDroop is something that you have to determine yourself.
How to see this in action:
If you have a CH IV board, you can watch this interesting BIOS bug work in real time. Attach a Voltmeter to the CPUv and the GND pin-outs on the board. This will give you a reading of the actual voltage being applied to the CPU.
What to do in the mean time:
Currently ASUS is trying their hardest to create a BIOS that gets rid of this bug. They have been working around the clock to make sure their customers are satisfied. As for now, the consumer has to bear with this little big. I say little because its really more of a headache rather than a major instability causing issue.
There are a couple work arounds that I believe would be appropriet for this situation. First you can easily leave the LLC on and figure out a voltage that will work with the OC. You should look for the bear min voltage in this case. For LLC will take care of the rest and will apply more voltage when needed. I would not suggest to keep the voltage at default 1.35, because LLC doesn't completely make up for everything. Its only designed to help a little. For example a 4.0ghz CPU requires about 1.41v to work 24/7. If you turn LLC on, you can get away with 1.38v in the BIOS.
The draw back to keeping LLC on is that you will not be able to fully control the temperature of your CPU anymore. This can cause instability with the higher OCs that some people are trying to achieve. If you are looking for a high OC, but you are already pushing that temperature to its breaking point, you can turn off LLC. Now the issue you are going to have is determining the exact VDroop you have. My suggestion is to start off with what you would normally use. For example a 4.0ghz CPU will use about 1.41v. With my board (VDroop may very please do not take my example 100%) I have a .05v VDroop. That means that I have to add .05v to the CPUv to achieve an actual 1.41v. So in my case a CPUv setting reads 1.46v, but the BIOS reads at 1.41v.
I hope this helps this helps.
As a side note I will be testing further to figure out how to make the best of this situation. I could use some help though since I don't have to much free time
As of now these motherboards are listed as to have the problem:
M4A89GTD-Pro (USB3 included)
M4A89TD-Pro
CH IV
Whats going on here? Here is the plain and simple fact of whats happening. When LLC is enabled, the correct voltage is applied to the CPUv but when the CPU is in need of more voltage, it is usually limited by the amount given. LLC allows the CPU to use more voltage, creating a much more stable environment. When LLC is turned off, a VDroop is applied to the CPUv. This drop in voltage can be anywere from .05v to .1v.
The VDroop is something that you have to determine yourself.
How to see this in action:
If you have a CH IV board, you can watch this interesting BIOS bug work in real time. Attach a Voltmeter to the CPUv and the GND pin-outs on the board. This will give you a reading of the actual voltage being applied to the CPU.
What to do in the mean time:
Currently ASUS is trying their hardest to create a BIOS that gets rid of this bug. They have been working around the clock to make sure their customers are satisfied. As for now, the consumer has to bear with this little big. I say little because its really more of a headache rather than a major instability causing issue.
There are a couple work arounds that I believe would be appropriet for this situation. First you can easily leave the LLC on and figure out a voltage that will work with the OC. You should look for the bear min voltage in this case. For LLC will take care of the rest and will apply more voltage when needed. I would not suggest to keep the voltage at default 1.35, because LLC doesn't completely make up for everything. Its only designed to help a little. For example a 4.0ghz CPU requires about 1.41v to work 24/7. If you turn LLC on, you can get away with 1.38v in the BIOS.
The draw back to keeping LLC on is that you will not be able to fully control the temperature of your CPU anymore. This can cause instability with the higher OCs that some people are trying to achieve. If you are looking for a high OC, but you are already pushing that temperature to its breaking point, you can turn off LLC. Now the issue you are going to have is determining the exact VDroop you have. My suggestion is to start off with what you would normally use. For example a 4.0ghz CPU will use about 1.41v. With my board (VDroop may very please do not take my example 100%) I have a .05v VDroop. That means that I have to add .05v to the CPUv to achieve an actual 1.41v. So in my case a CPUv setting reads 1.46v, but the BIOS reads at 1.41v.
I hope this helps this helps.
As a side note I will be testing further to figure out how to make the best of this situation. I could use some help though since I don't have to much free time
