FX Vishera series and CPU-PLL

[ShrimpBrime]

Are y'all sure the VDDA only runs the PLL?

PLL is Phase locked loop. Really the option to over volt this does little. Basically with electronics, this voltage is pretty much a set variable being the processor system is no more then a circuit. Your PLL bus speed would be 200 x multiplier. So PLL voltage would be added when running a higher PLL frequency. Since most people rarely use moer than 300 reference clock, raising PLL voltage will likely have little effect.

There's plenty more to it, variable frequency oscillator and a phase detector so on and so forth, but hopefully this is in the right direction.

From what I've come to understand, the VDDA voltage is a chipset bus voltage. Again, since the chipset reference clock is usually at a set point, so is the voltage.

If you see these voltages increase on auto, that's just how your bios was written while these voltages are in auto mode.

PLL voltage from 2.6 - 2.8v isn't a big jump. If 2.8v was the max setting, it's obvious that more than that would inherent circuit damage as warned in the owners manual of your hardware electronics.

All I really care to know about CPU PLL voltage is whether or not it improves my overclock (temps, stability, etc.)

Under extreme conditions maybe.

 

[RGone]

Yeah, we had pretty much hashed out what CPU_PLL was going to do and why I just told him to have some fun computering in an old resurrected thread. Some of the bios engineers called CPU VDDA as CPU_PLL for what reason is unknown.

I think the consensus back when this thread was still warm was that CPU_VDDA had some effect on some analog VRM motherboards, a lot more so than with the digital VRM mobos. I have not fooled with VDDA now in over a year so since it never proved out to do what some analog VRM boards seemed to do when tweaking VDDA. Nothing to write home about when I worked for hours and hours on my CHV. But I did give it a big-time go.

RGone...

 

[ShrimpBrime]

Yeah, we had pretty much hashed out what CPU_PLL was going to do and why I just told him to have some fun computering in an old resurrected thread. Some of the bios engineers called CPU VDDA as CPU_PLL for what reason is unknown.

I think the consensus back when this thread was still warm was that CPU_VDDA had some effect on some analog VRM motherboards, a lot more so than with the digital VRM mobos. I have not fooled with VDDA now in over a year so since it never proved out to do what some analog VRM boards seemed to do when tweaking VDDA. Nothing to write home about when I worked for hours and hours on my CHV. But I did give it a big-time go.

RGone...

Inherently, this is one voltage that I do overvolt, just for the sake of Just In Case.

If you are spending hours on this VDDA PLL voltage thing, I'd be interested in seeing 300 - 400 reference clocks and the effect of these voltages at that speed. Since reference clock will be up there in the clouds, I suspect a decent size afterburner with the proper fuel consumption would keep the craft air-born.