The C-States Intel introduced in all processors from the manufacturer 486DX4, and allow the processor to manage the power it consumes. However, as time goes by and especially if you want to overclock the processor, they can turn out to be a nuisance since they cause instability in the system as soon as the processor does not work at the frequency for which it was designed. In this article we are going to tell you how to activate and deactivate these C-States and if it is worth doing or not.
In short, Intel’s C-States or C-States are ways of managing power by the processor; Each of them uses a different amount of energy, it has quite an impact on performance. Seen from another perspective, the states range from 0 to 10 , with 0 being the normal mode that consumes more energy, while as the number increases, up to C10, the processor’s sleep mode increases, which consumes less but delivers lower performance.
How to enable and disable C-States on Intel platforms
Luckily, these power states are configurable from the BIOS to a greater or lesser extent (it depends on the motherboard and whether or not it is oriented towards overclocking), but they will always be a parameter that we as users can modify. As you will already suppose, these C-States are activated by default and to modify their configuration we will have to access the BIOS of the motherboard before the system boots.
As you can see in the screenshot above, with a Gigabyte motherboard, we can find this configuration in the Advanced CPU Core Settings section, or advanced configuration of the processor cores. Depending on the manufacturer of the motherboard and the generation of the Intel processor that you have these options we can find them in one or another section, but it will always have to do with the advanced options of the processor, and if you do not find anything specific as shown in the Capture above as C3, C6 or C7 states, you should always look for the C1E option.
In addition, as we have mentioned before, Intel’s C-States have been present since the old 486 of the brand, so even in very old computers you can find these options. Below you can see it in an AMI BIOS of an Intel Core 2 Duo E8600 processor.
Even here we have the “C1E function” that we talked about before, and it is the main one that you must configure depending on whether you want to activate or deactivate the C-States.
Why would you want to deactivate them and what are the consequences?
As we mentioned before, the C-States of Intel processors are power management modes, or we could qualify them as processor sleep states. Obviously, if you are overclocking your processor, you want to disable them since changing the processor power mode will cause instability, system hangs, blue screens, etc., and therefore it is always advisable to disable them before even starting to overclock.
The consequences of disabling these power modes include, for example, that the computer cannot go into sleep mode or hibernation, since for this to happen the processor must be able to put itself in the C3 state (it is the sleep mode, and all internal processor clocks stop). The same is true for hibernation, which uses states C6 and C7 (deep power save) whereby the CPU completely shuts down in addition to flushing the L3 cache.
