Intel cpu pll overvoltage

[rippy4500]

When I first switched to Intel I heard about these pll voltages and heard they were important, and when I first set up my system I played with them a little but didnt notice much, I noticed there was clock stretching but didnt know it was related to this.

 

After playing around with them again I realized that if the cpu pll voltage is too low there will be clock stretching. If its low like I had it before at +75mv my effective clock is lower than my active clock during a stress test but when I set it higher to +120mv I get a perfect 6000mhz on all cores. And I also noticed less microstuttering in games with this set properly.

 

After realizing this I set all the other pll voltages(memory controller, system agent, and ring) to +120 because Im worried it may cause the same problem if its too low there, I want to know if this is true or not or if these components do clock stretching at all, because im not 100% sure how to check those.

 

I also want to know if setting this too high affects the lifespan of these components, I didnt notice much difference in temps.

 

specs:

i9 14900kf, e-cores disabled and ht disabled, locked 6ghz all core and 5ghz ring.

ddr5 7200 cl34, 44, 44, 30 1.435v

gigabyte z790 aorus elite ax

rtx 4090 gaming x trio

[RONOTHAN##]

30 minutes ago, rippy4500 said:

I also want to know if setting this too high affects the lifespan of these components, I didnt notice much difference in temps.

It really shouldn't, the max you should be able to set those is +150mV by Intel spec, and everything I've seen has had that voltage be fine there. 

 

Realistically the PLL voltages for the IMC shouldn't really help that much for everything else, and these do usually sweet spot (I need to have them set to +105 on my 13700K for everything but IMC, which I have at +90) so don't think higher voltages help. 

[rippy4500]

24 minutes ago, RONOTHAN## said:

It really shouldn't, the max you should be able to set those is +150mV by Intel spec, and everything I've seen has had that voltage be fine there. 

 

Realistically the PLL voltages for the IMC shouldn't really help that much for everything else, and these do usually sweet spot (I need to have them set to +105 on my 13700K for everything but IMC, which I have at +90) so don't think higher voltages help. 

I havent noticed imc pll voltage affecting memory stability much. Maybe it would affect it more if my memory was overclocked to something crazy like 8000mhz+ but my mobo cant do higher than 7200 no matter what. What do you think?

 

Also how do these values affect clock stretching? Is it only cpu or the other stuff as well?

[RONOTHAN##]

23 minutes ago, rippy4500 said:

Maybe it would affect it more if my memory was overclocked to something crazy like 8000mhz+ but my mobo cant do higher than 7200 no matter what. What do you think?

It can help with 7200, though that depends more on the CPU, and from what I've seen it doesn't do a whole lot on 14th gen chips either. 

 

24 minutes ago, rippy4500 said:

Also how do these values affect clock stretching? Is it only cpu or the other stuff as well?

none of them really should, though AFAIK there's no clock stretching circuitry in the memory system, only the actual CPU core. 

[rippy4500]

1 minute ago, RONOTHAN## said:

It can help with 7200, though that depends more on the CPU, and from what I've seen it doesn't do a whole lot on 14th gen chips either. 

 

none of them really should, though AFAIK there's no clock stretching circuitry in the memory system, only the actual CPU core. 

I heard the memory controllers are better with 14th gen, not sure if thats true or not. I know I still cant get 7400mhz stable though and the option for 7300mhz was removed. Which timings benefit from a better IMC should I test?

 

I kinda knew that for the IMC. Im mostly worried about ring clock though, or does that not happen since I have a min and max ring frequency setting and they are both set to 5ghz. System agent I dont know much about though. Dont know why they cant add an option to disable clock stretching it would make this alot simpler.

[RONOTHAN##]

1 minute ago, rippy4500 said:

I heard the memory controllers are better with 14th gen, not sure if thats true or not.

On average yes, though individually it's more up to the silicon lottery. There are plenty examples of 13th gen chips being better than 14th gen for the memory controller. 

Madness!'s 13700K: tops out at 8266MT/s on 4 DIMM boards.

Buildzoid's 14900K: tops out at 7600MT/s on the same 4 DIMM boards. 

 

4 minutes ago, rippy4500 said:

Im mostly worried about ring clock though, or does that not happen since I have a min and max ring frequency setting and they are both set to 5ghz.

It shouldn't really happen, the ring AFAIK doesn't have clock stretching circuitry. The min/max ring frequency is more for something called Ring Downbin, where it will run at a lower frequency at certain points (the function of this depends on the board, ASUS boards do it differently than MSI boards and I've got no idea how Gigabyte does it). 

 

6 minutes ago, rippy4500 said:

System agent I dont know much about though

It's kinda like an interconnect between everything, this more affects stability than it does performance. 

[Islam Ghunym]

What I understood about PLL overvoltages is that it allows for less voltage drops in realtime in adaptive voltage scenario.

That should have no effect on the clock frequencies, but it can only increase the stability of your overclock (mostly won't even help stabilising your OC) They can reduce your chip's lifespan and barely do anything if at all. That's why it is better just to do the +offset instead. situations where PLL overvoltages can be helpful are extremely rare.

 

For why you are having better frequencies when playing around with them is perhaps a BIOS bug. CPUs these days are smart chips and they have too much of an auto behaviours at certain situations. You in someway triggered that, but PLL overvoltage have nothing to do with Memory or CPU frequencies. At least not directly in your situation.