AMD FX-6300 what is the correct voltage for 3.5 GHz ?

Thanks for reading my topic.

I want use an correct enough voltage value for AMD FX-6300 thus not wasting voltage and less heat and optimizing NB and RAM settings.

II links below is showed some voltages and frequencies about FX-6300.

voltage is 1.4

1400 MHz, 0.9V
2000 MHz, 1.025V
2500 MHz, 1.125V
3000 MHz, 1.225V
3800 MHz, 1.4125V
4100 MHz, 1.425V

Not any information about voltage for 3.5 GHz.

Mainboard is an Biostar A960D+V3 6-X and BIOS AMI version 8.00.15 ( mainboard BIOS version 2019-01-10 2.61 ).
That BIOS not allow core performance boost ( boost one core in 4,1 GHz and all cores in 3,8 GHz ).
The settings used are :

CPU/HT Reference Clock 200 MHz
Core VID = 1,2750
Core FID = 17,5 X
Core DID = Divided by 1
NB VID = 1,1750
NB FID = 2000 MHz
NB DID = Divided by 1

HT Link Speed = 1.8 GHz
HT Link Width = 16 Bit

The BIOS default value for voltage is 1,2750. That value is the correct default minimum voltage for 3500 MHz ?
I see if using HT Link speed with frequencies below of 2 GHz the mainboard northbridge is less heat.

I have done some tests changing HT and RAM settings. Not any performance loss or gain if using HT above 2 GHz or even DDR3 above 1333. DDR3 between 1066 and 1333 MHz the performance gain is less of 5 % being that performance gain is for database softwares.
Video card use PCI-E 8x thus I not see any gain if using an high HT link speed above 1.8 GHz.
I understand the NB VID and NB FID are related to CPU internall memory controller. I see in AMD docs the memory controller is 933 MHz ( 1866 MT/s ).

I not want any overclock.
Only information for FX-6300 about :
- correct minimum voltage value for 3500 Mhz.
- an good minimum voltage and frequency values for internal NB VID ( memory controller ) when using DDR3 in 800 or 1066 MHz.
- an good minimum frequency value when using DDR3 in 800 or 1066 MHz.
and also
- any optimized settings not being overclock to use in BIOS for tests.

Using an cpu voltage an bit below of default when the cpu is being used in 100 % can damage the cpu ?
If changing the CPU northbridge ( memory controller ) voltage and frequency in low values when using DDR3 in frequency above 1333 MHz can damage the cpu internal memory controller ?

Thanks very much for reading.
Have an nice day.
Last edited:


Posts: 1,882   +1,556
Generally undervolting or underclocking should not break CPU, memory controller or north bridge etc so doing it is pretty safe. There are exceptions though and anything can happen.

When there is no specified voltage for certain clock speed, you must manually search for that "correct" one that in this case is somewhere between 1.225V and 1.4125V.

For other questions, AMD specifies voltage and/or frequency values so that CPU works with them. If you lower voltage, AMD does not guarantee it will work. how much you can lower them, depends on exact CPU you are using so only way is to test certain settings and if it doesn't work, then probably voltage is too low. Just like with overclocking, there are no certain values that applies to all CPUs out there.


Posts: 2,744   +3,334
Staff member
1400 MHz, 0.9V
2000 MHz, 1.025V
2500 MHz, 1.125V
3000 MHz, 1.225V
3800 MHz, 1.4125V
4100 MHz, 1.425V

Not any information about voltage for 3.5 GHz.
Plotting those figures in Excel shows a linear correlation, up to 3800 MHz (it plateaus after that clock speed):


So 3500 MHz would be around 1.32 volts.