What disables Turbo Mode?

[Grestorn]

I've read many times that the Turbo Mode is disabled if the BCLK is set to any other value than 100.

Because of that and also because my two GTX 980 are only working with PCI 2 if I use a strap of 125, I want to stick to a BCLK of 100. I can overclock just fine that way, my DDR4 RAM even reaches 3000 MHz without any trouble.

But it seems that the Turbo Mode stays disabled.

So what exactly disables the Turbo Mode? Is it enough already to change the max. multiplicator? This would mean that you can either OC or use Turbo Mode - which is kind of stupid.

An indicator that the Turbo Mode is not active, by the way, is that the "CPU Package" wattage doesn't seem to be calculated correctly.

[LiveOrDie]

Like you said it gets disable when changing the BCLK off 100 in your bios in yellow font at the top does it say Target CPU Turbo-Mode Frequency ?

[Mosc_007]

Turbo mode is enabled or disabled depending on the CPU Mulitplier. Running a BCLK of 100 means the Turbo mode will be enabled with clock speed over 3.5 Ghz. (Multi > 35). If you use a BCLK of 125 to get the same Clock the Multi is Lower. Maybe 30. And with a Multi of 30 Turbo mode is dissabled. I stopped using a BCLK of 125 Mhz because of this. You don't need a BCLK other than 100 Mhz anyway. 3000 Ram will run with a BCLK of 100. Even though you can get the CPU Clock you want with BCLK of 125 Mhz the rest of the system will be slower. Because Turbo mode is off the Cache will only run at 3.2 Ghz no matter what the Cache Multi is on.


Charles

[Grestorn]

My experiments seem to indicate that I can increase the Multiplier just fine and Turbo seems to continue to work. But as soon as I change some voltages, this seems to affect the calculation of the current thats drawn by the CPU and therefore effectively disabling Turbo Mode.

But this is just based on the observation of the "CPU Package current" sensor value, and not really a conclusive test.