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

[augusto44]

Hello.
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.

https://www.techpowerup.com/cpu-specs/fx-6300.c1210
voltage is 1.4

https://www.cpu-world.com/CPUs/Bulldozer/AMD-FX-Series FX-6300.html

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.

 

[kerberos_20]

each CPU has different lowest voltage it needs at some clock, so, set voltage, run stress test and then repeat with lowered voltage untill unstable
that way youll find out what voltage your CPU can run at 3.5GHz

it also depends on mainboard quality as voltage can leak on cheap mobos

 

[augusto44]

Thanks for replying.

"run stress test and then repeat with lowered voltage untill unstable"
Unstable mean OS crashing BSOD ?
Doing stress test to reach unstable system can damage the cpu ?

 

[Viking2121]

Yeah, 1.4v is pretty high for sub 4ghz on the FX line in my opinion, my FX8320 was able to get to 4.5ghz at under 1.4v, I can't see the FX 6300 needing more for 3.5ghz.

My chip hit a wall at 4.8ghz at 1.45v, I do remember that, needed 1.52v with load line calibration peaking it to 1.54v to get to 5.1ghz, talk about keeping the thing cool, it was a challenge.

Anyway, as said, each chip will respond differently with voltage and not all will be the same, if you are locking it at 3.5ghz full time with no turbo, I would try to aim at 1.3v and stress test, if stable go lower on the voltage, until it starts to become weird or crashing.

Unstable doesn't always mean a BSOD, actually a BSOD in my opinion is good thing, its fast and easy to know its not stable, But unstable could mean programs crash randomly, or just weird behavior like the computer being much slower than normal, if the computer acts noticeable strange or things crash that normally never do before under volting or overclocking, thats unstable.

Good Luck!

 

[drea.drechsler]

Thanks for replying.

"run stress test and then repeat with lowered voltage untill unstable"
Unstable mean OS crashing BSOD ?
Doing stress test to reach unstable system can damage the cpu ?

The OS may crash and BSOD, some stress testers (like Prime95) might error when a core returns an incorrect value from a calculation. Either way, that can mean it needs more volts...or less Mhz.

Speaking of Prime95: it's really not a good 'stress' test for stability as it's utterly unreal with it's continuous and tightly nested loops of AVX code. If you use it for stability testing disable the AVX test routines. Another, much better, stability test is Cinebench20 as it's highly predictable of maximum case real-world all core work-loads. It also uses AVX code but in much more realistic doses so you will have confidence it's stable for that too.

Yes, stress testing can damage a CPU. Especially so if voltage is way too high and/or it has inadequate cooling. Many people have stress tested their CPU's to death by running ever higher voltages and allowing high temperatures while trying to find a maximum clock. Rule of thumb is FX processors should run no higher than 70C with voltage up to 1.425V, or with temperatures up to 90C no higher than 1.38V. That's voltage as measured under load with proper monitoring software or (preferably) a DVM at the socket backside, not voltage as set in BIOS. But those are ideal maximums for stress testing limits and not meant for 24/7 use. If your overclocked processor sees them extensively in daily useage you should back off settings to provide margin. How much is personal choice.

 

[augusto44]

@Viking2121

"My chip hit a wall at 4.8ghz at 1.45v, I do remember that, needed 1.52v with load line calibration peaking it to 1.54v to get to 5.1ghz, talk about keeping the thing cool, it was a challenge"

Using an copper heat sink air fan is much hard have temperature below of 65C using the settings above.
You had luck have an good temperature with that cpu.

"f you are locking it at 3.5ghz full time with no turbo, I would try to aim at 1.3v"
In moment using 1,275 and NB 1,075. Not any crashes and having the same temperature without less performance.

"drea.drechsle"

I not see an Cinebench20 version for Linux.
However have Phoronix Test Suite for Linux having several type of tests. Perhaps have an stress test there.

 

[DSzymborski]

Honestly, if you're trying to make a usable PC rather than just seeing how far you can overclock, just find a mild overclock that's stable and just leave it there. There's no real upside to overclocking a lower-midrange CPU from a decade ago on what was a pretty cheap motherboard that used the lowest-end chipset available (that was originally for AM2/AM2+). Trying to find an aggressive overclock is fairly likely to end up with the CPU running at 0 GHz, forever.

 

[augusto44]

You are correct about overclocking that type of cpu.
My topic is about the correct voltage in 3,5 GHz and I not want any overclock.

 

[drea.drechsler]

Honestly, if you're trying to make a usable PC rather than just seeing how far you can overclock, just find a mild overclock that's stable and just leave it there. There's no real upside to overclocking a lower-midrange CPU from a decade ago on what was a pretty cheap motherboard that used the lowest-end chipset available (that was originally for AM2/AM2+). Trying to find an aggressive overclock is fairly likely to end up with the CPU running at 0 GHz, forever.

Well...I disagree with your premise with respect to FX CPU's in particular, although not necessarily with respect to the low-capability AM3+ motherboards that were very common.

These CPU's are extremely overclockable to levels that make a very noticeable uplift in performance and about the only way they are relevant for their period...when done right. Right now I'm running an FX6300 at 4.6Ghz quite comfortably, well within safe temp and voltage limits. The overclock makes a genuine difference when playing many games. I personally don't think it's worth putting in the effort and expense of a vintage build based on one unless it's also overclocked correctly when the intent is to actually use it. Otherwise it's mostly a curiosity but that's good enough for many.

But I do agree the "low-end" AM3+ boards typically built around 700 and 800 series chipsets can be a problem. But not because of the chipset: it's the VRM's they had as so many had no over-temp protections and would burn up when overloaded for too long. But even the low-end, 3+2, VRM designs can hold an FX6300 at a mild overclock of 4.1 or 4.2 Ghz though. As it were, that's also about where most people stop: just enough to get the turboing clock full-time.

Regarding the 8 core CPU's...especially those fire-breathing FX9000 CPU's...well that's another matter entirely, of course.

 

[drea.drechsler]

You are correct about overclocking that type of cpu.
My topic is about the correct voltage in 3,5 GHz and I not want any overclock.

The CPU operates across a range of possible voltages depending on processing load and P-state while turboing or idling. So the most correct is the stock voltage with BIOS settings at defaults; use the "optimized defaults" setting in BIOS (or reset CMOS) to do that.

Of course the processor will doubtless operate stable with lower voltage than that at each P-state, how much lower depends entirely on silicon quality.

 

[Viking2121]

Yes, stock is to load bios defaults and make sure ACHI is enabled so you can boot unless you set to ide mode when you installed your OS, and don't touch the CPU voltage or clocks, thats stock. There is range of voltage and its going to change if you install it on a different board, if you disable turbo it will still change voltage on the fly, Thats the reasoning behind my reply, there just isn't really going to be a right answer as each CPU and board is different, even between the same model you will see vastly different compared to pretty much anything back when Turbo wasn't a thing.

When I got mine to 5.1ghz stable, it was during winter, and I sat my AIO the og H100 in the window so cold air would pass threw it, worked well but not practical, I ran 5ghz daily and it was always right on the thermal limit, never crashed or shutdown due to heat, but I would run it over 70c daily. I lost that chip due to how ya know AMD CPU's are, PGA, pulled a cooler off it and the CPU stuck to the bottom, and bent like all the pins on 1 side. I tried to save it, broke pins off and said screw it, I ended up buying a FX8320e as my brother was using it and I felt bad I broke it lol. Never really pushed that CPU, left it stock, in fact I just sold it today on Marketplace with a 990fx board and 32GB of ram for $100 bucks, was fun while it lasted, but time for it to go to a new home.

 

[Avro Arrow]

Impossible to say because every piece of silicon is different.