Overclocking amd 955 to 4ghz, Blue screen

One you could try increasing your voltage if your still under the thermal limits, which you apparantly are. Increase to 1.45volts test again. if that doesn't work you might want to try increasing your northbridge frequency from 2000 to 2200 @ 1.25 volts. if that doesn't work try cpu voltage 1.45 volts, northbridge @ 2400 mhz and at 1.3volts. before increasing your voltage on your northbridge make sure it stays no more than 53 degrees celsius. The max voltage to run through your cpu should be between 1.55volts and 1.5volts (within the fact that you can maintain the temps associated with those volts). now, don't let the northbridge get over 1.35 volts.

What you're trying to do is once you get to that 3.8ghz + range you may need to overclock other parts of your system. such as, the NB because it controls data flowing through the processor and your L3 cache of 6mb. In simple terms the cpu is going so fast that the other parts of the system may not be able to keep up. If none of that works 3.7ghz on a 955 is good man that's a 500mhz increase. Goodluck and read this guide to make sure you understand what's going on  

Dolk's guide to OC
http://www.overclockers.com/forums/showthread.php?t=596...

Tried with 1.45v still got bluescree. I'm trying with with 1.475v (I'm guessing the voltage here is the problem, I have to find the right voltage but I saw people reach stable with 1.425v but I guess every chip is different)

to be perfectly honest most people need to shove 1.5 volts + into their cpu (that i've seen). If you get 1.425 volts at 3.7ghz that's pretty darn good for a 955. Those dudes are really lucky if they only have to put a simple 1.425 which i believe a little higher than the max stock voltage. shove 1.475 volts and give it a shot

I went straight to 1.475v before I saw your post, CPU temps are at about 47.5C. I'm using AMD overdrive to overclock. I see the NB voltage slider but I don't see NB Freq. slider.

This is what I'm looking at.


When you say "before increasing your voltage on your northbridge make sure it stays no more than 53 degrees celsius." do you mean NB temp no more than 53C or CPU temp no more than 53C

1.475v seems to keep my CPU stable at 4ghz without playing around with those other settings. Temperatues havent gone over 48C which I believe is good. I was not able to stress for a long time but I'll try to stress for a few hours later and see how that goes.

I had a 3.7ghz stable at stock volts

1.475v, crashed during 3d11mark benchmark

That's good to hear  . What i meant was don't let the northbridge get over 53 degrees celsius. Second, The northbridge can be overclocked using the northbridge multiplier or the FSB. since your doing a multiplier overclock on your cpu, use the multiplier cpu/nb slider in amd overdrive. BEFORE you do that MAKE SURE that CPU/NB isn't getting over 53 degrees. the max volts to shove through the NB is like 1.35 volts. apparantly it sounds like your close to a 4ghz overclock. if prime 95 fails within a couple of hours i'd try upping the cpu/nb multiplier. Do 11x (then test), 12x (test), then 13x (then test) all using voltage of 1.25.

Well, you do know that going from 3.7GHz to 4.0GHz is only a difference of 8% right? At best you will probably only see a performance increase of about half of that in games if the game depends on the CPU. For games that are not CPU dependent as long as it does not hold back the GPU you will see 0% improvement. Crysis 2 is an example.

I guess it's about bragging rights...

I'm a little confused, sorry. Multiplier cpu/nb slider is the one thats at x20 right? Is there a way to monitor CPU temps and NB temps seperatly?

When you said this "Do 11x (then test), 12x (test), then 13x (then test) all using voltage of 1.25" im guessing you are refering to the Cpu/nb multiplier but I dont see that in amd overdrive. And when you said "voltage of 1.25" , thats NB voltage right?

my bad, it seems that amd overdrive isn't displaying the Cpu/nb multiplier... for some odd reason. you may have to go into your bios and change that usually it's called cpu/nb multi and it's default is 10x. yes, the voltage of 1.25 is the cpu nb. For now i'd try running 1.5 (on idle) volts through it and see if it's stable then mess around with the northbridge later. Some motherboards only support monitoring the cpu/nb through the bios. other software simply list it as the "motherboard temp"

4ghz at 1.5v passed benchmarking but crashed few minutes into far cry3. I think I'll leave it at 3.7ghz or 3,8ghz. This CPU is almost 4 years old and it was constantly running at 3,7ghz.