Overclocking AMD x4 955BE C3

[Crom!]

Hello guys,

I have searched for threads and fourms on how to overclock the phenom II X4 955. Most of them were useful but the OP's that started those topics failed to return to describe their results. Anyways, I know the 955 is an older cpu and every one is on about the new FX lines but I still haven't jump ship away from the AM3 socket yet.

Getting on with the point. My zalman cpu cooler just died and to replace it I just got the Corsair H100i water cooler. My temps, at stock settings, is consistent at 33-34c idle and 41-42c full load (currently 30c ambient). Before with the Zalman it was 48-49c idle and 55-57c full load....I never dared tried over-clocking lol.

So now that I have a water cooling setup I have started to try overclocking which I haven't done since my old Pentium 4 2.4 ghz Northwood socket 478 (got that sucker up to 3 ghz )

With setting the CPU vcore to 1.425 volts and the cpu multiplier to 19.5 I managed to achieve 3.9 ghz stable (38c idle and 46c full load). I did manage to get 4ghz with the multiplier at 20 but when I tired to run starcraft 2 my system BSOD.

I hadn't tried anything else. Right now I have my system back to stock settings. My goal is to hit 4 ghz. I am sure it can do it but i could use some help getting there. Can anyone help me with this please? My system specs are as the following:

Case: Antec 900
Motherboard: Gigabyte 790XTA-UD4
CPU: Phenom X4 955BE 3.2Ghz C3
Ram: Corsair 8GB DDR3 1600 mhz (stock speed)
PSU: Corsair HX650 (650 watt)
Video: XFX HD6850
Cooling: Corsair H100i (push config) modded to fit inside case
HDD: WD-500GB Black edition
OS: Windows 7 Home premium

Thank you

 

[RGone]

1.425V on the cpu may well n0t be enough for cpu stability at 4.0Ghz. It might be that simple. No one can say what voltage your cpu will have to have to run 4.0Ghz. IF you think that 3.9Ghz was stable then go there and test as below and attach results as outlined below. That is where we have to start when we cannot see your keyboard or monitor screen. Luck man.

This is what we need to see for sure and a real good starting point.

Normally during setup and testing we disable C1/E, C6, Cool N Quiet, APC, TurboCore and in windows performance manager itself we set to "performance" mode. That way there are not "other" settings messing with the overclocking process. Some of those settings are not available on all models of cpu but where in evidence we disable for setup of overclock process.

CPU Tab in CPUz from CPUID com

Memory Tab in CPUz from CPUID com

SPD Tab in CPUz from CPUID com

And this is screen capture of HWMonitor (free version) from CPUID com
HWMonitor has been scrolled enough and large enough to show Min/Max of Voltages and includes the CPU CORE TEMPS / "package" temps fully visible. Latest versions of HWMonitor show the CPU Core Temp as " a Package Temp" and is only shown as a single temp since there were never multple, individual core temp sensors anyway.

This capture is made of HWMonitor after it has been open and running on the desktop logging Min/Max temps and voltages while Prime 95 was running Blend Mode test on all cores for at least 20 mins and then the capture of HWMonitor was made and it shows the Min/Max temps and voltages before P95 Blend was started and while running P95 Blend mode and gives much greater insight into how the system is performing without guessing.

In order to attach screenshots of INDIVIDUAL images as suggested, first crop and capture the images with Snipping Tool found in Windows Accessories or equivalent. Then click on Go Advanced, a button at the bottom of every new post window. Then click on the little paperclip tool at the top of the Advanced post window when it opens. Clicking on the paperclip tool brings up the file browser/upload tool and the rest is fairly obvious.

 

[Johan45]

Welcome to OCF Crom!
I know you've read some guides but I find Dolk's quite good and will help you understand the realtion of the different busses.
As Rgone says 1.425v is likely too low for an OC of 4.0. more likely 1.45-1.5v is more realistic and you'll need to do some stress testing with something like Prime95 blend to ensure stability. Starcraft isn't going to load the system enough to be considered stable.

 

[manu2b]

^^Agreed.

My 955 needed 1.48v for 4GHz and 1.55v for 4.1Ghz IIRC while 1.4 was enough for 3.9GHz.


A tad more volt should certainly fix the unstability.

 

[Crom!]

Ok guys I did what you all suggested and here all the results:

Before overclocking:

 

[Crom!]

after overclocking and testing with prime95:

In my original post I did say that full load was at 48C but that was using starcraft 2 which obviously is not a good test, With prime95 I end up getting a max temp of 59c. Also i said that the voltage for the 3.9ghz was at 1.425 volt and testing with Prime95 had failed. Setting the voltage to 1.475v did the trick. Anyways I tired going to 4ghz @ 1.5volt and prime95 kept crashing causing BSOD. I didn't try go beyond 1.5volts. Sadly I think 3.9ghz is the best I am going to get out of this. My final settings are 19.5 for the multiplier and 1.475 volts for the cpu.

 

[RGone]

That core/package temp of 59c is probably a reason for the failure of P95 Blend mode. We have seen many that went beyond 55c that began to have instability beyond that 55c marker. Not everyone but enough see it that we suggest 55c as sort of tops for the core/package temp.
RGone...

 

[Crom!]

Well I did had my corsair H100i running at full fan speed, but maybe since the radiator is inside my case could be the reason why it hit 59c. Clearly the antec 900 was not deigned for this type of cooling setup. But anyways I am somewhat happy with the results. Better than nothing. Here is what rig looks like with h100i inside the case. Thanks for all your help

 

[RGone]

You get what is available until the temp becomes a problem and then better cooling is the only choice if one wants more speed. Realstically there is a useful limit. Some 955BEs are beasts and many are just plainly not. When not is the situation...nothing really helps that is reasonable for aveage day to day use for hours at a time.

Good luck using your rig and glad you got what was there.
RGone...

 

[Johan45]

Yes that rad position is going to do nothing but limit it's function. I had one in an Antec 1200 with the same issues. I ended up pulling the big top fan out and jimmying it into that spot . It worked a lot better. One other thing as mentioned in the guide I linked you should have your CPU-NB speed up around 26-2700 for that speed. It can actually help stability.

 

[Crom!]

Yes that rad position is going to do nothing but limit it's function. I had one in an Antec 1200 with the same issues. I ended up pulling the big top fan out and jimmying it into that spot . It worked a lot better. One other thing as mentioned in the guide I linked you should have your CPU-NB speed up around 26-2700 for that speed. It can actually help stability.

Alright I will try that but before I do that, other than adjusting the voltage on the CPU are there any other voltages I have to adjust? Here is my bios screen for overclocking (i had to adjust the picture to fit everything so it looks a little off)

 

[dtrunk]

you could up the NB Freq one notch, and confirm it jumps it up in CPUz memory tab; i believe for a decent overclock you can take it up to 2200'ish.

beyond that, your memory timing is loose. looks like the memory should be set to 9-9-9 24 41 2t 1.65v; i would see if you can run these timings at 1.6v or maybe compromise and see what you can get away with at 1.5v. mayb some of the other guys here have a thought on this.

overall, nice overclock. dont push the chip to 1.5 and be happy at 3.9ghz; personally i'd even take it back to 3.8ghz, dial in the memory, and be happy.

 

[Crom!]

Final settings:
CPU: 3.9Ghz @ 1.475v
NB-Freq: 2.4 Ghz @ 1.25v
Memory: 9-9-9 25 41 2T @ 1.65v
Idle temp: 38c
Load temp: 46c

Thanks all for your help. Good learning experience.

 

[Mandrake4565]

See if you can get the Nb Freq to 2600 the C3 stepping 955's usually can.