Question Why is my 4 core i5 6500 using 3 and the 4th is non existent

[ArticFrost]

My Cpu used to run on 4 cores and now that i downgrade it uses 3 cores and the 4th one isn't working or popping up

 

[TechyInAZ]

Go into your motherboard's UEFI/BIOS and make sure all 4 cores are enabled.

 

[ArticFrost]

Go into your motherboard's UEFI/BIOS and make sure all 4 cores are enabled.

It only says 3 still

 

[TechyInAZ]

What motherboard do you have?

Sometimes cores will be numbered as such:

First Core = 0
2nd Core = 1
3rd Core = 2
4th Core = 3

Because computer language dictates that you start with the number 0 not 1.

 

[ArticFrost]

i have dell and i have 3 cores not 0123 just 123