i7-3820 OC

[diamondmines]

I just increased the multiplier and base clock in the bios to get to 4.2GHz, torture test has been made around 2-3 hours, no problem. But when I restart the machine, the monitor loses its signal. When I shut down and restart the computer, I get signal and boot into desktop.

Can anyone suggest something to solve this problem?

Thanks.

My specs:
ASUS P9X79
i7-3820
32GB DDR3 1600MHz CL9 Corsair Vengeance
XFX HD7750
Contact 30 as cooler.
Cooler Master 750W + 80 Plus Bronze

4.2GHz TEMPS:

25C on idle, 55C on full load.

[Thorsson]

I presume that you have 4 sticks of memory. Have you tried it with just 2?

I don't have any recent experience with Cooler Masters, but reading around it appears that quality control is somewhat lacking. In three reviews two gave it awards, but the third said it was dangerous to your components under load. Equally user reviews on Amazon have some who reported problems that were fixed by swapping the PSU. If you can try another PSU then that's worth a try.

[diamondmines]

Oh my god, that would be a problem - I've just got it new. Wouldn't 750W + 80 Plus enough for at least 4.2GHz. The cpu tops at 3.8GHz with turbo boost anyway. And I do have 4 sticks, yes. I wonder that might be the problem too. I know about the stress it puts on the IMC. However, perhaps I should try with 4.0GHz first and then go up little by little and see what comes up. I don't think it should be concerned with the PSU - but then again, you may be right. If it is the PSU after all, I will have to give up overclocking it because I won't spend another 80 dollars on the psu.

What do you think about the Vcore? I think on default (it's 1.275volts). Should I increase it a little?

[Thorsson]

The problem isn't the power, it seems to be more one of quality control - units that should be rejected are going out.

I would try to isolate the problem, and that means seeing how 2 sticks do. If they have the same problem then you know that's not an issue. I would think that 1.275V should be more than sufficient for 4.2GHz, but if your heat is under control then you could up it. It doesn't sound like a CPU problem though. What I imagine is that your boot sequence is getting stuck part way through. I'm not familiar with the ASUS P9X79, but there are warning lights on the Deluxe version - do you have any?

BTW there's a review of that motherboard and details of overclocking with a i7 3820 here. It may give you some help.

[diamondmines]

I will try taking out 2 sticks and then try. If that doesn't work, I will make the Vcore to 1.280/85. I do see a red light coming up but I can't read what it is. I will resort to the manual for that. Thanks for your help for now Thorsson. You've been great

[Thorsson]

I see that Cooler Master changed OEM on this product in 2011 and most of the reviews are on the old version. One that is not

[diamondmines]

I think I've got it right this time. I got the OC guide from JJ-ASUS guy. Here were the tweaks I did:

BCLK - not modified.
CPU Strap - not modified.
CPU Ratio - x43 - 4.3GHz
CPU Gen Filter: Enabled
Memory: 1600MHz
CPU Power Management: C1E, C3, C6 and C7 all ENABLED.
Anti-surge disabled.

I haven't played around with VCore. But when I Prime 95 it, the max I see is 1.338volts. Is this a dangerous Vcore to max to? How would the life span of my CPU be effected by this Vcore overall? When idle, it drops to 1.070. I guess it looks fine but if there is a problem or if I have adjusted something not necessary, please tell me guys.

Thanks a lot so much for your help. From 3.6GHz stock to 4.3GHz with an entry level cooler like ThermalTake Contac 30, I have achieved my first and (hopefully) successful overclocking-that's 700MHz over here, lol. I feel reminiscent of Pentium II-350MHz and Pentium III-450MHz CPUs now.

[diamondmines]

BTW, my temps on FULL LOAD on Prime 95 was 61C. But it was instabled. It kept lingering between 59-60-61 degrees Celsius. On idle, it's 26-27C. What do you think about the temps?

[madman045]

I have the 3820 with the P9X79 Pro, using just the Asus software, i set the BCLK to 125 and the CPU ratio to 37 and that's it, 4.6GHz all day long, max temp 61c gaming

[Thorsson]

BTW, my temps on FULL LOAD on Prime 95 was 61C. But it was instabled. It kept lingering between 59-60-61 degrees Celsius. On idle, it's 26-27C. What do you think about the temps?

That's fine. Your VCore is OK too. Intel says it's fine up to 1.4, but I'd feel happier closer to 1.3 personally.

[diamondmines]

I think you're right. I will try to manually config. the Vcore and I will start from 1.295 and go up slowly 0.005 increments in each case and then reboot for the best stable voltage. Thanks again man.

[diamondmines]

Some people have stated on rog.asus.forums that 1.338volts on the vcore is pretty high and it will hurt my cpu. Because it was on auto mode, it only went up to 1.338 on full load prime 95. What vcore should I not pass for 4.3GHz, I don't think I want to go further with this thermaltake contac 30 cooler...

Thanks.

[Thorsson]

Well 1.25 is the default on an i7-3820, so 1.338 doesn't seem all that high, although theoretically the chip will run at 1.05.

You are getting Turbo Boost to take it up, just like it throttles down on idle. You can go two ways - fix the Voltage lower, but you won't get throttle back, you'll be at full power the whole time; change the offset value so that it runs lower when boosted, but that probably will affect your OC ability. You will need to experiment to find the right offset level.

[diamondmines]

I've given it a 1.280Vcore but the voltage doesn't drop down when idle, it stays on 1.28. It passes Prime 95 with 1.280 at 4.3GHz but I want it to undervolt when it's 1.2GHz idle. It doesn't do that. I have tried the offset but it looks complicated. Should I turn off Turbo Boost? How should I manage this? What really does the offset do? The min offset is 0.800v and I don't know how it works.

Thanks.

[Thorsson]

That looks like the maximum offset, minimum should be something like 0.005. And it can be negative.

Anyway offset isn't what you're after from your post, it's about EIST. EIST should already be enabled. You may need to enable C1E. BCLK must be 100 for it to work.

Turbo Mode should not take you above your specified power, current and temperature limits, and is needed for overclocking. You may simply find that the motherboard says 1.28V when you set it to 1.2V. Whether it's correct then only a multimeter could tell, but assuming it is, you could set it lower.

[diamondmines]

I have like tweaked and restarted 20 times and couldn't get it to work at 1.280/1.290 when on full load (Prime 95) since it doesn't crash on this Vcore and throttle back at idle to 1.100volts. For the life of me, I just want to ask for the record, is this VCORE at 1.280 deteriorate my cpu 27/4? Let's think about it in this way: If I did no overclocking and my system loaded on default values, how long would it last? (I know this depends on the cpu but in general). And if I run my cpu at 1.280volts 27/4, how much % of the lifespan of the cpu would I be losing? I hope I've made my self clear. Thank you so much Thorsson for giving me everything I need.