What's wrong with my overclocking?

[dexter98]

I just started overclocking yesterday, basically all I did was set AI Overclock Tuner to X.M.P., and changed the multiplier, I didn't touch the voltage. CPU Voltage is set to Offset Mode and CPU Offset Voltage set to Auto.

I started with 43X multiplier, ran prime for 10 mins and increased it to 44X, ran prime for another 10 mins and finally increased to 45X for 10 mins of prime. I plan to do a full prime test tonight but I'm little concern about the CPU voltage. When I go into BIOS, it shows me the CPU voltage of 1.278 - 1.288, but in CPU-Z it's showing Core Voltage of 1.432 - 1.440 idle, and fluctuates between 1.392 - 1.400 running prime. Temperature wise, the highest in my 10 mins prime test is 86. I think it's weird that CPU-Z is showing higher voltage when idle than running prime.

My question is, why is my bios reporting different voltage than CPU-Z? Which is the more accurate voltage? If CPU-Z is more accurate, then 1.440 is way too high right? I think all the OC articles I read have voltages between 1.285 - 1.35, that does mean I should manually set my CPU voltage?

Here are my specs:

i7 3770K

ASUS P8Z77-V Pro

Noctua NH-D14

G.SKILL Ares 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) 8-8-8-24

 

[Cons29]

first off, im not an expert but ill try to help.
basically it would be better to have more control, dont set it to auto. auto is a wild card, so better put some (safe) values there, you dont need to set all voltages, some can be left in auto.
then test, if it fails maybe it needs more juice or you've hit a wall or something. just remember the limits, good luck

 

[CrArC]

I just started overclocking yesterday, basically all I did was set AI Overclock Tuner to X.M.P., and changed the multiplier, I didn't touch the voltage. CPU Voltage is set to Offset Mode and CPU Offset Voltage set to Auto.

I started with 43X multiplier, ran prime for 10 mins and increased it to 44X, ran prime for another 10 mins and finally increased to 45X for 10 mins of prime. I plan to do a full prime test tonight but I'm little concern about the CPU voltage. When I go into BIOS, it shows me the CPU voltage of 1.278 - 1.288, but in CPU-Z it's showing Core Voltage of 1.432 - 1.440 idle, and fluctuates between 1.392 - 1.400 running prime. Temperature wise, the highest in my 10 mins prime test is 86. I think it's weird that CPU-Z is showing higher voltage when idle than running prime.

My question is, why is my bios reporting different voltage than CPU-Z? Which is the more accurate voltage? If CPU-Z is more accurate, then 1.440 is way too high right? I think all the OC articles I read have voltages between 1.285 - 1.35, that does mean I should manually set my CPU voltage?

Here are my specs:

i7 3770K

ASUS P8Z77-V Pro

Noctua NH-D14

G.SKILL Ares 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) 8-8-8-24

Oh lawd. Stop. Now.

NEVER overclock with auto voltage. It will not be frugal in applying crazy overvoltages to get results. Try setting everything back to normal and examining the voltages at idle/load in CPU-Z, and look how different they are.

Your BIOS voltage - where are you reading that from? A system health/monitoring window or just a setting field?

Regarding your idle voltage is higher than your load voltage, sounds like Vdroop. This is where the load on the VRMs causes a voltage drop (in case you were wondering, this load can be an enormous 80-120A for a high-end CPU). This isn't a problem in and of itself, in fact it's by design. The crazy voltages are another story.

Normally your idle voltages will be very low, but it sounds like your system has elected to nail Vcore up at silly voltages to ensure stability. Rarely is this necessary unless you're going for stupid clocks and I always recommend keeping a chip's power-saving features (like dynamic Vcore) active when overclocking for daily use. Change your offset voltage to "normal" or "0.00" if you want dynamic voltage with no overvolting at this stage. When you want to overvolt, you can use the offset to allow the system to control voltages like normal but also apply more at every power stage. This is my favourite way of doing things and you end up with a very cool-running but fast system

 

[A Bad Day]

In my personal definition, I consider certain voltage levels unsafe if they give diminishing returns. Especially if the processor is running at 70C to 90C.

For example, 1.000 to 1.050 V gave a 400 Mhz boost, then 1.051 to 1.100 V gave a 700 Mhz boost, but then 1.101 to 1.150 V only gave 300 Mhz boost, and 1.151 to 1.200 V only gave a 50 Mhz boost.

1.35V can actually be harmful, because no one really knows the safe volt level. And Intel is not going to risk extra RMAs by announcing a "safe" volt level.

 

[dexter98]

Ok I changed the CPU Voltage to manual and set it to 1.300V, it's showing as 1.320V in CPU-Z, and I ran prime for 45 minutes, the highest temperature was 91.

Is 91 normal for stress testing? I think my CPU fan is already running at its max speed ~1200 RPM, so there's no way I can reduce temp further through fan. What should be my next move, lower the CPU voltage a little more? Thanks.

 

[steddora]

91C is really hot. I don't go over 70C if I can help it. Pushing 1.3v into an Ivy Bridge processor isn't good. You should start at like 1.000 like A Bad Day said. Then work your way up to give/take 1.2v. Once you see your temperature difference between 1.3v and 1.2v you'll cry.

 

[dexter98]

Ok here's the update, it seems like the logical way to overclocking is start off with a low voltage and gradually increases voltage until it reaches a stable overclock. For me, I worked in a totally different direction lol. I started with 1.440V (which was auto), then decreases it to 1.35V, then 1.30V, and then 1.25V.

I wasn't sure if I wanted to spend the night running prime at 1.25V just in case it might get too hot. So I lowered it even further to 1.20V, and I got my 1st BSOD just minute or two after running prime. Over the next few hours, I tried 1.225V, 1.230V, 1.240V, and 1.245V and ran prime for 30 minutes with each voltage. No BSOD but I always get a fatal rounding off error with 1 of the 8 workers, sometimes 10 minutes of testing and mostly 30 minutes into testing.

Finally I bumped it back to 1.250V and the fatal rounding error disappeared, and I realized that 1.250V might be the minimal voltage I need so I ran it overnight for 9 hours with 0 error or BSOD, and the highest temp was 85.

So my question is, is this a good overclock? Is 1.250V and 85 temp for 9 hours of prime ok?

I'm totally new to overclocking, I shut down/start/restart/changed BIOS setting like hundred times yesterday, does that hurt the hardware?

 

[rdc85]

If u wanna to keep that speed u will need better cooler.... (water cooling, maybe? )

or u will need to down the speed (multiplier) and search the lowest voltage for that new speed setup.....

I dunno about intel ivy but running above 70c sound dangerous
(it reminds me my old pentium D that actually hit 100c , it makes my room like an oven )

 

[steddora]

85 is a bit warm. rdc is right you're going to need better cooling if you're going that high. You're going to have to drop the voltage otherwise.

1.440v on your 3770k and it didn't pop? Tough chip I say. 1.4v is just dangerous territory with the 3770k. Like I said before, I wouldn't go over 1.3 on one of them myself and it reminds me of why I stick with my 2600k. I run 4.6Ghz at 1.3v and stay below 70C.