Question hwmonitor shows different clock speeds

jostegogar

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Mar 26, 2019
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hey guys in my bios it says that 1 core is running at 4.2GHz 3 core at 3.9GHz and 2 core at 3.8GHz but the hw monitor shows all cores running at 4GHz which one is more accurate?
CPU intel core i5 8400
mobo prime Z370
 

Karadjgne

Titan
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Both. There's no set speeds, the cores will bounce around according to temps, boost, usage etc. Bios and windows are seperate and respond seperately, according to how fast its read. Speeds can change in milliseconds, 4.2 to 3.8 and back to 4.2. If Hwmonitor doesn't read the speed change when it happens, it'll just stay at 4.2.

Never been a fan of Hwmonitor, it was decent back when it was written, but there's too much changed, especially about how mobo's read, respond, addressing, speeds etc.

Hwmonitor reads one temp on my Z77 as 255°C, another temp as -125°C and my 12v rail as 8.23v. Not likely scenarios.
 

jostegogar

Reputable
Mar 26, 2019
300
29
4,740
Both. There's no set speeds, the cores will bounce around according to temps, boost, usage etc. Bios and windows are seperate and respond seperately, according to how fast its read. Speeds can change in milliseconds, 4.2 to 3.8 and back to 4.2. If Hwmonitor doesn't read the speed change when it happens, it'll just stay at 4.2.

Never been a fan of Hwmonitor, it was decent back when it was written, but there's too much changed, especially about how mobo's read, respond, addressing, speeds etc.

Hwmonitor reads one temp on my Z77 as 255°C, another temp as -125°C and my 12v rail as 8.23v. Not likely scenarios.
not just hw monitor cpu z also shows all cores running at 3.9GHz. msi after burner show all core at 3811Mhz. each application is giving me different speeds lol. and i dont know which one i should trust