Overclocking the Athlon II X4 750k

[Warrgarbl]

Hello everyone,

I have recently built a PC for use during my work breaks. It consists mainly of parts that I could get for free from damaged customer PCs. I added an Athlon II X4 750k which I bought for half the price and an MSI FM2-A85XA-G65. The PSU is a 1000W OEM-branded Superflower unit and I use a CM Hyper 212 Evo as heatsink. My intention was to have an overclockable system so that I could make it a project and learn something new.

The problem that I am currently having is that I do not know where to get a program that gives me accurate temperature readings. Each program gives me different temperatures which is really confusing, to say the least.

What do you guys use? I would also be thankful for general hints regarding AMD OCing, what to be wary of and the likes.

The attached picture shows some temp readings while running prime95 large inplace FFTs and Furmark for 10 minutes, case closed, with 30+C° ambient (it's hot in here).

 

[RCoon]

HWInfo is what I use for CPU temps.
NICE PSU MAAAAN :O
AMD OC'ing is easy. 200 base clock, change the multi between 18 and 24 for desired OC.
Set CPU VCore to manul and aim around 1.3v-1.4v, not too much, hyper 212 isnt made for insane volts.

 

[Cyclops]

I've been using Core Temp as far back as I remember. It's been pretty consistent with pretty much every CPU that I've tested, most of those processors have been from Intel though.

From that screenshot, it looks to me that you're running the processor on stock frequency and voltages. If that is the case, with your cooling, the temperature reading from the Core Temp is pretty accurate. Keep in mind that AMD measure their thermals differently than Intel as the TJ max is always quite lower for AMD chips.

PS: You should be able to hit anywhere from 4.4 to 5 GHz depending on the quality of your silicon.

 

[Warrgarbl]

Thanks for the infos. I am leaning towards HW Monitor, even if the temperatures it shows seem to be on the high side. Better safe than sorry. I did not have time yet to try anything, but I wonder if replacing my 200mm side fan which only blows like 10% of its air towards the CPU with a 140mm in the top fan mount would improve temperatures.

Currently I have 2 120mm intakes in the front, 1 200mm intake on the side panel, 2 120mm exhaust fans at the top of my case and the usual 120mm exhaust at the back of the case. I have read that turbulences can happen with side fans and that those potentially decrease cooling efficiency.

The attached pic shows the 200mm fan and its positioning.

 

[RCoon]

Thanks for the infos. I am leaning towards HW Monitor, even if the temperatures it shows seem to be on the high side. Better safe than sorry. I did not have time yet to try anything, but I wonder if replacing my 200mm side fan which only blows like 10% of its air towards the CPU with a 140mm in the top fan mount would improve temperatures.

Currently I have 2 120mm intakes in the front, 1 200mm intake on the side panel, 2 120mm exhaust fans at the top of my case and the usual 120mm exhaust at the back of the case. I have read that turbulences can happen with side fans and that those potentially decrease cooling efficiency.

The attached pic shows the 200mm fan and its positioning.

I had a 230mm fan on my side panel and it improved GPU cooling, now I run with the side panel off entirely because of watercooling.
Side panel fans do more to help than they do harm. I think your side panel fan is fine. I've had crossed air flows in my case for years and it still remains a fair few degrees colder inside the case than the ambients of my room.

 

[Warrgarbl]

The point is that I feel that the parts of my PC that need the most cooling - my CPU & VRMs - receive little to no air from that fan. The GPU should be fine either way, but don't you think that a high mounted 140mm fan will move much more air towards the CPU area of my board?

 

[RCoon]

The point is that I feel that the parts of my PC that need the most cooling - my CPU & VRMs - receive little to no air from that fan. The GPU should be fine either way, but don't you think that a high mounted 140mm fan will move much more air towards the CPU area of my board?

CPU wont get cooler from a side fan very much at all, that's down to the CPU cooler, VRM's will though.

 

[Warrgarbl]

I assumed that by blowing cool air on the heatsink I would actually reduce the ambient temperature for the CPU heatsink which should help cooling it. But if you say that this has almost no impact then I am going to believe you.

By the way... my BIOS show me an idle temp ~7° cooler than HW monitor does in Windows. Can I assume that HW monitors temperatures are too high? Or is this a normal difference?

 

[RCoon]

I assumed that by blowing cool air on the heatsink I would actually reduce the ambient temperature for the CPU heatsink which should help cooling it. But if you say that this has almost no impact then I am going to believe you.

By the way... my BIOS show me an idle temp ~7° cooler than HW monitor does in Windows. Can I assume that HW monitors temperatures are too high? Or is this a normal difference?

The heatsink will have its own airflow, anything interupting that is likely to worsen the airflow and cooling as oppose to making it better. Blasting a plane with 200mph winds from all angles isnt going to make it fly forward better.
There are a few different temperatures you're seeing. Package temp, Core temp, they are going to be different. One will always be higher than the other.

 

[Warrgarbl]

Okay, I have the CPU at 40x ratio with 1.35V and the NB at 1800 instead of 1600 at 1.25V. Voltages were chosen rather randomly because they seemed safe. I gained 15° under prime95. I suppose there is still some headroom. AMD OverDrive states that I have 37° on all cores, but I have no idea how far I am from the maximum temperature. HW monitor is at 86° package.

However, I have quite a hard time understanding how CPU, northbridge / hypertransport and RAM interact. My target was 4.4Ghz+ on the cpu, with ram at 1866Mhz (I have 2x 4GB Corsair Vengeance 1600 CL9 @ 1.5V).

Any hints or maybe a link to a good tutorial would be great, it seems as if it is rather hard to find information that is valid for the little Athlons.

EDIT: Okay, 4.2ghz @ 1.375V / 2Ghz @ 1.2V with marginal temp increase. Since I'm heading home soon I will leave prime95 running over the weekend and see if it still runs when I get here on monday... or if I set our building on fire

 

[Warrgarbl]

So, I seem to be stable at 4.32Ghz @ 1.4V. However, if I go any higher than that, even with dramatic voltage increase, prime95 becomes unstable. Temperatures are fine.

Am I correct to assume that I have hit the highest OC possible for my CPU?

 

[RCoon]

So, I seem to be stable at 4.32Ghz @ 1.4V. However, if I go any higher than that, even with dramatic voltage increase, prime95 becomes unstable. Temperatures are fine.

Am I correct to assume that I have hit the highest OC possible for my CPU?

4.3Ghz is a very good overclock! I wouldnt be too unhappy with that, and 1.4v is a decent voltage. Once you hit 4.4 and above you'll have to pour more volts in it, and the returns you get for voltage become less and less. I'd probably stop at 4.3-4.4 as the compute performance increase is not worth the heat it puts out.

That being said, you can probably hit 4.6 on around 1.45v +- 0.05v either side.

 

[Warrgarbl]

Yes, I was aiming for 4.4Ghz. However, if I increase the CPU to 4.4Ghz I am unstable, even if I use 1.475V (didn't want to go any higher, was just a quick test). So I suppose I will not be able to go any higher.

Now, there's still the NB. I currently run that at 2Ghz (stock is 1.6Ghz). Is there a real benefit in overclocking the NB as well? I had a look around and it seems common to run it at 2.4Ghz.

Also, if I start to OC my RAMs - Latency, then frequency? And can I assume that once I run my CPU and NB stable with stock rams that I will not have to touch CPU and NB again, no matter what I do with my RAM?

 

[RCoon]

Yes, I was aiming for 4.4Ghz. However, if I increase the CPU to 4.4Ghz I am unstable, even if I use 1.475V (didn't want to go any higher, was just a quick test). So I suppose I will not be able to go any higher.

Now, there's still the NB. I currently run that at 2Ghz (stock is 1.6Ghz). Is there a real benefit in overclocking the NB as well? I had a look around and it seems common to run it at 2.4Ghz.

Also, if I start to OC my RAMs - Latency, then frequency? And can I assume that once I run my CPU and NB stable with stock rams that I will not have to touch CPU and NB again, no matter what I do with my RAM?

NB needs to run at a higher frequency to RAM to run properly. OC'ing you're RAM, you might get 1866 if you drop your timings down to CL10, but the performance gains will be 1% maybe. Knock the NB to 2400 and test stability. I personally dont OC RAM because its pointless for my uses in gaming.

 

[Warrgarbl]

I basically agree to what you said about gaming and ram. However, I just want to try to get the most out of this system. Like I said in the original post, it's a little project. I'll try that and see how it turns out, thanks for the info.

EDIT: Bumping the rams up to 1.872Mhz without latency changes seems stable. I'll have it run overnight and see if it survives that.