Big jumps in Q9450 core voltage

[carinae]

Hello I have a problem with my Q9450. I recently overclocked it from the stock 2.66 GHz to 3.6 GHz (450x8). I still have some problems getting this to run stable (several BSOD's during prime95 runs) so I decided to increase the core voltage to 1.296V.

The problem is, when my system is idle it uses the voltage I set in the bios (1.296V) but every few seconds it jumps to a higher voltage of 1.312V. When running prime95 the exact opposite happens, the core voltage is decreased to a number lower than that which I specified in the bios and then it jumps up and down.

 

Should I increase the voltage even more for a 3.6 GHz overclock on a Q9450? It's wierd though because if it didn't get enough during prime95 then why would it switch to lower voltages.

 

Could use some help here Thanks.

 

Specs:

 

- Intel Q9450 2.66 GHz (overclocked to 3.6 GHz (450x8) / 1.296V core)

- ASUS Striker II Extreme (NB 1.47V / SB 1.50V)

- Tagan 800 watt PSU

 

Here, I've also made an image that shows when the system is idle it uses a voltage much higher than I specified in the BIOS, yet when it is on full load it uses a voltage lower than that specified in the BIOS.

 

[ebarone]

Do you have a setting called "Load Line Calibration" set to enabled?

 

The voltage level switching is on purpose, although I'm not sure why it would go above what you set in the BIOS. Check this thread here to understand why its doing that.

[Flibo]

At least according to my experience voltage always drops when the chip is under load.

[carinae]

Do you have a setting called "Load Line Calibration" set to enabled?

 

The voltage level switching is on purpose, although I'm not sure why it would go above what you set in the BIOS. Check this thread here to understand why its doing that.

 

I'll check it out, I think LLC is off.

 

At least according to my experience voltage always drops when the chip is under load.

 

Yeah that seems to be happening to mine aswell, but I need that higher voltage to prevent getting BSOD's in prime95. I tried using 1.32V on the core but then the screen would turn black when loading into Windows and nothing happens.

[Nicckko]

Hello,

 

That is called Vdrop or Voltage Drop, you will experience it if you have the Cpu Load Line Calibration disabled. The Cpu Load Line Calibration increase the CPU Voltage a little bit when it is under load.

 

[carinae]

I have another small problem, I didn't feel like making a thread so I'll ask it here. After overclocking the CPU some of the sound in games becomes distorted. This only happens in game menus and so on, it doesn't happen with the actual game sounds or when I'm listening music.

[kingdingeling]

Yea, that'd be Vdrop / Vdroop, totally normal that the voltage drops when stressing the CPU more.

 

The sound problem I have no heard of, however that does sounds like an unstable overclock, considering you said it only happens when you've overclocked.

[carinae]

I searched on Google and I found that increasing the FSB to overclock your CPU might also affect your soundcard, this could be why the sound is sometimes distorted. I think I'm going back to 3.4 or 3.5 GHz because I can't get 3.6 GHz stable.