Overclocking GA-P67A-UD3 OC'ing Questions!

Followed this guide but Windows crashed upon loading (I'll get to this in a minute), reset a few options and it boot into Windows but lasted about a minute before BSODing. Please bare with my probably rediculous questions .

There's a fair few more options in this BIOS compared to previous ones I've used so I just wanted to go through some of them and get some advice.

BCLK/DMI/PEG: Not really sure what this is or how it affects the overclock.

System Memory Multiplier (SPD): My one is set to 13.3 (1333 MHz) in the BIOS but my RAM is rated at 1600 - probably a stupid question but I take it I should boost this up to x16?

Real-Time Ratio Changes in OS: I'm guessing this allows the cores to run at different priorities and change these once in Windows, as opposed to being fixed. By default this option is off, any advantage to turning it on?

C1E, Thermal, etc.: These are familiar power saving options but is there really any advantage to leaving them off once a stable overclock has been achieved (if your computer is idle, why run the CPU at its maximum voltage?).

Load-Line Calibration : Helps with vdroop?

QPI/VTT(VCCIO): I've only meddled with Vcore for the CPU before, no idea about this one.

System Agent Voltage (aka VCCSA): Same as above.

DRAM Voltage: The guide says to put it up to 1.65. By default it's at 1.5, any reason to change it up? If I change the memory multiplier from 13.3 to 16 will this require those extra volts?

Ok, now onto the reasons for why Windows wouldn't boot initially.

PCH SATA Control Mode: Mine is set to IDE, the guide says ACHI. When I rebooted with this changed to ACHI this seemed to cause Windows to lock up in the loading screen and BSOD. Am I missing much of a performance boost with this set to IDE? Any way to change it without reinstalling?

HPET Mode: I have Windows 64 bit but in the BIOS it's set to 32-bit (this might have actually also cause Windows to crash upon boot, I haven't had time to check yet). Again, am I really missing out on much if I leave this to 32 bit?

Sorry for the long-winded post, it would actually be quite useful if CPC had some kind of glossary on these terms so it's not so much of a black box.

 

Ok first things first, switching from IDE to AHCI is going to cause lock ups because windows doesn't have the right drivers installed to use it properly. There is a guide and a few tips here on how to do this without re-installing windows. If this doesn't work and you really want AHCI then a re-install is the only other way. Unless you have a SSD drive it's not essential to have AHCI enabled, it won't affect your overclock.

Your CPU's speed is dependent on 2 things, the BCLK (which is set to 100) which also affects your motherboards speed and memory speed, and the CPU multiplier which in your case can be increased without affecting the rest of the system and putting under more stress. So you multiply these figures together and get your CPU speed in MHz.

Just out of interest how far have you tried overclocking to? It might be worth reducing the multiplier a little to see if it's stable. I'd also keep the BLCK at 100 for now as with sandy bridge, more devices are reliant on this clock, including PCIe and the disk controller which aren't really overclockable.

If the BCLK is at 100 then by all means set the memory multiplier to 16 to get it running at the speed it should. Be aware that if it doesn't run stable (with everything else at stock speeds) then it may just be a case of adjusting a few memory timings but we'll discuss that if and when we get to it.

I'd approach the overclock by increasing the multiplier a couple of steps at a time to start with (one step at a time later) and see if the system boots up. When you start getting crashes you are going to need to increase the Cpu's voltage slightly until you get stability back. 2 things to note:

The faster you run your CPU and the more voltage you apply to it, the hotter it will get and the more power it will draw.

Just because it boots into windows doesn't mean it's 100% stable, it's not under much stress at this point so it's best to run something like the Prime64 torture test for a long time to see if it gives any errors. I wouldn't be happy with an overclock unless it could run this for at least 24 hours, but when you are initially seeing what your system is capable of you can probably run it for half an hour at a time to test if it is initially stable at that speed/voltage. Always keep something like Argus monitor or Coretemp running while you do this so you can get an idea of what temperatures you are getting.

Once you start reaching higher speeds you might need to turn LLC on to stabilise the voltage when it goes from idle to stressed. Best to use CPUz to check what the voltage is registering as before and after you do this as for some reason on my motherboard it raises it to a figure that is higher than what I set it to in the bios. Very important to keep an eye on this as you don't want to put more voltage through your CPU than is necessary.

As for power options, I achieved my 3800MHZ by keeping Turbo on (for which you need the power saving modes to be enabled). Some people don't think this is a pure overclock but for me it achieves the clock frequency I want without drawing too much power or stressing my system too much. Seeing as there is nothing I use that uses the full potential of my CPU, any higher would be a waste and possibly shorten it's lifespan. I guess if you were wanting to achieve a very high overclock it, you might be able to get it higher by turning power saving features off for stability.

Going to be out for the rest of the day but I'm sure there are plenty of people here with enough experience to help you with any other questions you have.

 

(Un?)Fortunately I do, so I guess I'll go about hunting for this guide

As per the guide, I cranked it right up to x45 (i.e. 4.5 GHz). This is not the way I've OC'd in the past but I thought I'd give it a try. At the moment it's at x34 (default is x33) and it's been running F@H, all 4 cores at 100% for over 24 hours with a little gaming as well. Not that I'd expect a crash with such a pitiful OC.

Roger that. I was just curious as to why it wouldn't have recognised the RAM as 1600 in the first place

Thanks for the info, I think I should just go back to incrementally OC'ing it. Still confused about some of those options though..

 

Sorry, just updated the previous post with the link I forgot to put in

Does F&H tell you if it gets errors in calculations? this is why Prime64 is so useful, an overclocked computer can still give errors without crashing if the voltage isn't high enough.

Most Bois' will default memory to safe speeds and timings to avoid any issues on first bootup. You can configure it yourself afterwards.

I've only got a P55 board so I've not seen all the options for myself as they are new to P67.
Which ones are you still confused about?

 

No errors in F@H but as I say, it's only 100 MHz OC'd at the moment (I actually meant to return it back to default 3.3GHz but must have accidentally set it to 3.4). I'll fire up Prime95 when I get home from work and overclock a bit more.

The bits I'm still not 100% on are: Real-Time Ratio Changes in OS, QPI/VTT(VCCIO), System Agent Voltage (aka VCCSA), DRAM Voltage (does it need to be higher if I increase from 1333 to 1600?), HPET.

Thank you.

 

Any idea what your memory voltage should be? If the sticks are designed to run at 1600 at their rated voltage you shouldn't need to increase it any more, but sometimes like i mentioned before, the bios can default to different settings so it's best to double check.

This might help with some of the other questions you have.