Trying to learn... Going for slight overclock!

[Dieter01]

System:
Motherboard: ASUS M4A79T Deluxe, Socket-AM3
CPU: AMD Phenom II X4 965 Black Edition Quad Core (@3.8Ghz, 1.5V)
RAM: Kingston DDR3 HyperX 1333MHz 4 x 2GB DDR3, CL7-7-7-20, 1.7V
Case: Fractal Design Define R2 Titanium Grey
PSU: Cooler Master Silent Pro M700 700W
GPU: XFX Radeon HD 5770 1GB GDDR5
HDD: WD VelociRaptor® 300GB SATA, 10000RPM, 16MB, 3 GB/s
CPU cooler: Corsair H100i with 2 x Noctua NF-F12 PWM fans (top exhaust)
Fans: 2 x 120mm front (NF-P12, intake) , 140mm bottom (NF-A14 PWM, intake), 120mm rear top (NF-S12A PWM, exhaust)
Operating System: Win 7, 64 bit


Two objectives I would like to achieve with this thread: First to run the RAM at its XMP spec, then afterwards to get a very slight, stable overclock (more for the learning than a need for speed...).

These were the CPU-Z data before I started tweaking a little:

... Then I tried to set the BIOS according to the rated frequency and timing the RAM is rated to. I also increased the RAM voltage from 1.5V to 1.66V. My Memory tab now looks like this:

Most guides tell you to enable XMP in the BIOS though. I have not been able to find that on my BIOS version. After wathcing a few videos I see that most other ASUS motherboards allow you to set the "AI overclock tuner" to XMP. Mine only has Auto or Manual though. I used the manual when achieving the setting in the picture above. Is everything now as it should be or am I missing something that should have been obvious?

 

[Johan45]

Nope looks like you got the ram set up. XMP doesn't appear in most AMD boards since it's a memory profile based on intel specs. AMD used to have AMP , that lasted for a few years but most memory manufacturers dropped it since there wasn't any money in it, is my guess.
As for the Overclock , your voltage is getting up there already for 3.8, if that's what it actually need you're probably getting close to the end of the journey for a decent 24/7 overclock.

 

[Dieter01]

....

As for the Overclock , your voltage is getting up there already for 3.8, if that's what it actually need you're probably getting close to the end of the journey for a decent 24/7 overclock.

Yeah, I was a bit surprised as well. I'm probably stuck with a not-too-great chip. But no worries, I am not (too) concerned with the actual gain in performance. When I bought this machine some years ago I wanted to have a go at overclocking but was afraid to ruin components. Changing voltage in BIOS scared me to be honest. Now the machine is older so I am having fun trying things while still being able to sleep at night, hehe. This is a learning experience for me, I am reading forums, guides, watching videos and using google...

RAM seems like a much more difficult subject than other types overclocking though... I will do some stress testing to verify that my current setting runs stable, after that I am not sure where to start. Most guides to overclocking RAM explain timings, the difference betwen C, tRCD, CMD and so on... Few say where you should start. I am thinking I should try to lower my timings rather than increase frequency (not even sure if my motherboard can handle a higher frequency) but I will try to read up a bit more first. Any good threads or links I should have a look at?

 

[Johan45]

To increase performance at that clock look to the NB speed. You're still at 2000, bringing this speed up really improves ram throughput. If you have a test like Aida64, it can show you any gains you might make with NB and ram tweaking. With ram timings it's more of a drop the number and see if it's stable or will boot. A lot depends on the actual ram but also the IMC in the CPU. At 1333, I wouldn't be surprised if you could manage to drop the CL to 6. The only way to know is change it and test.

 

[Dieter01]

Tried the 7-7-7-20 @ 1.66V but system crashed. Increased voltage to 1.7, still not table. Increased CL now from 7 to 8 and running Prime95 just to see if it is possible to get a stable reading. I downloaded Aida64 (trial version). Ran the memory benchmark there for the first and last of the three settings mentioned above. How do I use this data? Or should I be looking at other data?

From what I understand the RAM is guaranteed by the manufacturer to be stable at the spec I am not able to achieve above. But I guess there must be a reason why the MB doesn't automatically select the XMP profile as well, if it was easy and always stable with every combination of equipment that would have been the standard.

Is it possible that I might have to adjust NB or the CPU/NB ratio to get a stable system at 7-7-7-20?

 

[redduc900]

Is it possible that I might have to adjust NB or the CPU/NB ratio to get a stable system at 7-7-7-20?

Yes, especially w/ 4 x 2GB installed.

 

[Dieter01]

I increased the CPU/NB frequency and it had great effect on Benchmarks. I also increased CPU/NB voltage from 1.2750 to 1.2875V and NB voltage from 1.100V to 1.160V. DRAM voltage is still at 1.7 (up from stock 1.5V). This setting was much more stable than when I tried the same RAM timings (7-7-7-20) with all the NB settings on Auto.

It isn't entirely there yet though, it crashed after about 1.5 hours on Prime95 blend. There are so many variables now! Where do you suggest I go from here (and why)? Loosen the timings or work on the voltage and frequency? Should I still leave HT on standard settings?

 

[Johan45]

Aida says you're running the ram at 7-7-7, I would give the ram a try at 7-8-7-21 and CR1 if it'll do it. Also bump that NB up even higher.

 

[Dieter01]

When you say bump NB... Do you mean frequency, voltage or both?

Ohh, and just to be a bit more precise on my previous post. I said crash, but it was in fact just Prime95 stopping due to a wrong roundoff. If that makes a difference or sais something about how close to stable the system is.

 

[Johan45]

Ya it's not a crash but calc error. Either way get that NB speed up to 26-2700 , you might need to add voltage maybe notyou're getting near to 1.3v which should be enough but based on your CPUs behaviour so far it might not be. Right now though maybe we should get it stable with the ram setting before we bump up the NB.

 

[Dieter01]

Success!

Stable for 10 hours on Prime95 after bumping voltage to 1.3V, NB @2600 and adjusting timings according to what you suggested - including CR1.

Benchmarks for this 7-8-7-21 CR1 setting was actually better than 7-7-7-20 CR2 (which was unstable). Is that due to CR1 being faster, or due to 7-7-7-20 CR2 not being stable?

Also, why did we increase the timings we did? Why increase tRCD instead of tRP for instance? Should you try to keep the timings close or does that also depend?