[SOLVED] Windows 10 lowering my overclock

[harpnart]

I have a B85M-DS3H-A gigabyte motherboard and an i5 4670K, which I've overclocked in my bios to 4.3 GHz. In the BIOS, it correctly displays this clock, but when I boot into Windows 10 and check CPU-Z, it's at 4.2 GHz. How do I prevent this from happening?

 

[USAFRet]

4.3 <-> 4.2 could easily be just a rounding error in what is reading and displaying it.
In any case, that is a 2.4% difference.

 

[harpnart]

BIOS vs CPU-Z
That's a pretty big rounding error

 

[USAFRet]

BIOS vs CPU-Z
That's a pretty big rounding error

3%

Different applications may read things differently.

 

[harpnart]

Ok true. Just did 4.5 and this is what's showing up: 4.5 GHz

 

[USAFRet]

Ok true. Just did 4.5 and this is what's showing up: 4.5 GHz

And that could easily be a limitation of CPU-Z.

 

[harpnart]

Alright, I guess I shouldn't worry about it then. Thanks!

 

[lordmogul]

I both CPU-Z screenshots it shows the multi at 42x (despite showing a maximum of 43x and 45x), looks more like it gets limited somewhere else. Might be the max CPU power state in windows power plan or some other software.

 

[harpnart]

I both CPU-Z screenshots it shows the multi at 42x (despite showing a maximum of 43x and 45x), looks more like it gets limited somewhere else. Might be the max CPU power state in windows power plan or some other software.

I don't think I have any software that would limit. My windows power plan is on high performance.

 

[Karadjgne]

Could be multiple things. Some motherboards, bios lists BCLK as 100.00 and yet if you check cpu-z it'll come back as 99.0 - 100.9 at times. That can even change with cpu-z editions. I've run the original vs asus rog vs msi editions and there are differences. Even versions differences can have different results.

You assume 100 numbers, as in the OC is 4200 MHz for a 4.2GHz or 4300MHz for 4.3GHz, but honestly if the BCLK is a little whacked out, you could see 4249MHz as 4.2GHz and 4251MHz as a 4.3GHz OC, far less than the 2-3%.

 

[hotaru.hino]

Measuring clock speeds accurately isn't a trivial task. You could go by what you set in BIOS, but that's just a number in some CMOS storage device, not the actual clock speed. You could try doing frequency counting, but even then oscillators are not perfect and clocks will drift pretty badly (I had a microcontroller drift minutes per hour in a basic test).

Honestly, as long as the reported speed is within spitting distance (like <5%), it's probably fine.

 

[Karadjgne]

Nobody likes the term 'Margin of Error' but everybody must assume one, especially given the speeds of today's processors, ram, quality control on components and materials etc. Most having to deal with such would prefer 5% or less, but if it's 6% in reality, the only fix is new mobo, cpu, gpu etc.

Sometimes 'Good Enough' is just that, good enough.