Help Overclocking AMD FX-8120

[NykoEdits]

Hi All, I recently tried to overclock my FX-8120 to 4ghz. As soon as I started a Prime95 stresstest my CPU speed dropped from 4036mhz to 2869mhz and toggled between the two values, never saying stable.

 

Here is my rig:

AMD FX-8120 at 3.1ghz, trying to get it to 4ghz (its on aio water)
EVGA GTX 1070 (this is the reason I am trying to overclock my cpu)
16gig of DDR3
Gigabyte GA-970A-UD3 

 

I was watching an old Jays two cents tutorial on how to overclock my cpu. His motherboard was (obviously) a lot nicer then mine and, I could not find some of the settings he said to change in my bios.

Could someone who knows these things write out a list of the things I need to change? 

I have extremely new to overclocking, and I really don't want to blow up my CPU.

[themctipers]

don't use p95 for stress testing, that is using AVX

don't forget to monitor your temperatures

 

[kb5zue]

26 minutes ago, NykoEdits said:

Hi All, I recently tried to overclock my FX-8120 to 4ghz. As soon as I started a Prime95 stresstest my CPU speed dropped from 4036mhz to 2869mhz and toggled between the two values, never saying stable.

 

Here is my rig:

AMD FX-8120 at 3.1ghz, trying to get it to 4ghz (its on aio water)
EVGA GTX 1070 (this is the reason I am trying to overclock my cpu)
16gig of DDR3
Gigabyte GA-970A-UD3 

 

I was watching an old Jays two cents tutorial on how to overclock my cpu. His motherboard was (obviously) a lot nicer then mine and, I could not find some of the settings he said to change in my bios.

Could someone who knows these things write out a list of the things I need to change? 

I have extremely new to overclocking, and I really don't want to blow up my CPU.

Overclocking 3.1 to 4.0 is a big jump.  Keep an eye on the temps.

[Ravager911]

@NykoEdits

I had the same motherboard back then.

The VRM´s are overheating pretty quick on that board.

As soon as the VRM´s are getting to hot, the cpu clockspeed is reduced significantly.

Try to direct more airflow on the VRM heatsink.

[Sauron]

Sounds like an overheating issue. Don't use prime95 first of all, it places the cpu under unnatural stress. Use something like cinebench.

37 minutes ago, NykoEdits said:

I have extremely new to overclocking, and I really don't want to blow up my CPU.

Then start off with small increases, moving up by 1GHz at a time is asking for trouble. Maybe your cpu can only get to 3.7 without losing stability - if you go straight for 4ghz you'll never know and you'll be stuck in endless troubleshooting that leads nowhere. Go up 100mhz at a time until you start getting problems, then revert to the last stable setting and start moving up by 10-20mhz at a time until you find the best spot where it's still stable.

 

It's unlikely you'll damage the cpu unless you touch voltage, but the motherboard may not be as sturdy.

[NykoEdits]

1 hour ago, Sauron said:

Sounds like an overheating issue. Don't use prime95 first of all, it places the cpu under unnatural stress. Use something like cinebench.

Then start off with small increases, moving up by 1GHz at a time is asking for trouble. Maybe your cpu can only get to 3.7 without losing stability - if you go straight for 4ghz you'll never know and you'll be stuck in endless troubleshooting that leads nowhere. Go up 100mhz at a time until you start getting problems, then revert to the last stable setting and start moving up by 10-20mhz at a time until you find the best spot where it's still stable.

 

It's unlikely you'll damage the cpu unless you touch voltage, but the motherboard may not be as sturdy.

I ended up getting 4ghz 'stable'. Temps are between 20c to 31c idle and 40c to 45c under load. 

Using cinebench, the cpu speed stayed solid at 4ghz.

Out of curiosity, I reverted back to fail safe defaults and ran prime95. Sure enough, CPU speed was bouncing between the boost clock (~3.4ghz) and ~2.89ghz (the same speed it would get to under prime95 during my stress test at 4ghz.) 

 

Motherboard problem do you think?

[Drak3]

9 minutes ago, NykoEdits said:

I ended up getting 4ghz 'stable'. Temps are between 20c to 31c idle and 40c to 45c under load. 

Using cinebench, the cpu speed stayed solid at 4ghz.

Out of curiosity, I reverted back to fail safe defaults and ran prime95. Sure enough, CPU speed was bouncing between the boost clock (~3.4ghz) and ~2.89ghz (the same speed it would get to under prime95 during my stress test at 4ghz.) 

 

Motherboard problem do you think?

Sounds like the CPU isn't getting enough voltage to run an AVX workload at those clocks. Instead of crashing, it clocks itself down to a stable point.

 

Or thermals and clocks under AVX load are just wack under your chip.

Are those temps good for Prime95? What software you using?

[Sauron]

52 minutes ago, NykoEdits said:

I ended up getting 4ghz 'stable'. Temps are between 20c to 31c idle and 40c to 45c under load. 

Using cinebench, the cpu speed stayed solid at 4ghz.

Out of curiosity, I reverted back to fail safe defaults and ran prime95. Sure enough, CPU speed was bouncing between the boost clock (~3.4ghz) and ~2.89ghz (the same speed it would get to under prime95 during my stress test at 4ghz.) 

 

Motherboard problem do you think?

if on cinebench it stays at 4ghz then I blame prime95 and you should be fine. prime95 messes with the voltage and can cause bizzarre behaviour.