How to reduce minimum CPU clock speed?

[DylanAi]

I have an Intel Core i7-5930k which, according to Open Hardware Monitor, has a 1200MHz minimum clock speed. Is there a way to reduce the minimum clock speed without affecting the maximum clock speed (which I currently have set to 4GHz with automatic voltage)? If so, is this okay or is it advisable to keep the 1.2GHz minimum?

 

[mdd1963]

As long as you have not specified full performance modes and/or fixed multiplier in the BIOS, and choose Balanced in Windows power plan, it should ramp the clock speeds down automatically in low-load conditions; most mainstream (6700, 7600K, 8700K, etc) Intel CPUs idle down to 800 MHz or so, but, perhaps with the HEDT, INtel and MB manufacturers might have chosne a higher minimum clock speed...(*seems to be the case if you are never seeing lower than 1200 MHz in HWMonitor)

(There might be no way to set that lower, I suspect that's an Intel/BIOS thing that you might not be able to manipulate further)

 

[DylanAi]

As long as you have not specified full performance modes and/or fixed multiplier in the BIOS, and choose Balanced in Windows power plan, it should ramp the clock speeds down automatically in low-load conditions; most mainstream (6700, 7600K, 8700K, etc) Intel CPUs idle down to 800 MHz or so, but, perhaps with the HEDT, INtel and MB manufacturers might have chosne a higher minimum clock speed...(*seems to be the case if you are never seeing lower than 1200 MHz in HWMonitor)

(There might be no way to set that lower, I suspect that's an Intel/BIOS thing that you might not be able to manipulate further)

Thanks for your response. I use the balanced power setting in Windows 10 and a multiplier in BIOS (40 x 100MHz), but even at the 3.5GHz base clock speed, I've never seen the CPU run lower than 1200MHz. The reason I ask is because I've seen 800MHz minimum clock speeds in PCs using i7-6700k, i5-7600k, i5-8600k, and i7-8700k CPUs; those are all newer models, though, and I have seen another thread from someone with a 5th gen Intel (the i7-5960x) who also reported a 1200MHz minimum clock speed, so it could very well be a 5th gen Intel limitation. If that is the case, I'm fine with it, but if it's possible to get lower idle CPU clock speeds with my i7-5930k without under-volting it, I'd like to know how.

 

[InvalidError]

PLLs used to generate clocks have upper and lower design limits, 1200MHz might simply be the lower limit that Intel designed into those CPUs. On my i5-3470, 1600MHz appears to be the minimum I can get by setting the maximum CPU power state anywhere below 50%.

As CPUs get more powerful via extra cores, multi-threading and IPC gains, it makes sense that Intel would extend the minimum clock range for better power efficiency under light loads.

 

[mdd1963]

FYI, several other folks' HWMonitor screenshots of 5930K testing a few years back are also showing 1199 MHz or so for minimum, so, I highly suspect that's the predetermined bottom end clock speed for those models...

 

[DylanAi]

Thanks for the responses. Seems like 1200MHz is as low as the 5th gen Intel CPUs get.