Too low Voltages??

Breath_of_the_Dying

[H]ard|Gawd
Joined
Jan 8, 2007
Messages
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Hi guys, I was wondering if it would be bad to have too low voltages. I'm new to OC and did some tinkering with settings, and they seem to be low compared to what I've been reading online.

Here's what I have
Asus P6T SE
Core i7 920 (D0 stepping)
Corsair XMS3 6gb (3x2gb) DDR3-1600
Zalman 9900 CNPS cooling
AS5 thermal paste
Win7 Pro
CoolerMaster HAF922 (with 2 more 120mm fans on the side).

Using the ASUS corevoltage program, here's what I've set things to.
CPU voltage: 1.187
DRAM Voltage: 1.56
QPI/DRAM Voltage: 1.2 (as low as it can go)
BCLK Freq: 190
Multiplier: x20 (so 3.8)

I haven't done extensive testing, but Prime95 ran at least 15 min without issues. In that short time, the temps seem to hover around 70c on the hottest core.


Another thing, I'm noticing my core0 and core1 temps are around 4-6 degrees hotter than core2 and core3. Is that normal? I'm thinking there's a bubble in the thermal paste, but want to know if thats normal before applying paste.
 
Hi guys, I was wondering if it would be bad to have too low voltages. I'm new to OC and did some tinkering with settings, and they seem to be low compared to what I've been reading online.

The lower the better (lower temps, longer theoretical CPU lifespan). Running below spec voltages won't hurt the components, but it can cause instability. If its stable then be happy. :)

I haven't played with any I7 hardware yet so I can't comment on your specific settings.

Another thing, I'm noticing my core0 and core1 temps are around 4-6 degrees hotter than core2 and core3. Is that normal?
That's normal in my experience. Core 0 gets a bit more use than the other cores, so the area around core 0 (including core 1) gets a few degrees hotter.
 
Thanks for the info. It seems I spoke to soon, 3.8 became unstable once every few hours at that voltage. However, 3.6ghz is running pretty (so far) at 1.175v.

voltages.png


I did some informal benchmarking (ie running fraps while playing games) and there's no noticeable difference between 3.6 and 3.8. So I'm going to keep it at 3.6 until I feel I need the power (even 3.6 is probably overkill).
 
Doesn't 1366 have auto voltage control like 1156 does? On my 1156 mb I don't have to play with any voltages to OC because if set to auto the voltages change automaticaly on the fly as needed. I'm running stable at 4.0ghz with i5 750 and my temp tops out at 75c using prime95. CPU can handle that temp so I expect it is because 1.175v is just not enough to run stable with things like prime95. Legion Hardware OC same cpu I have to 4.2ghz and their temps were 95c in prime95 but still stable. I just check my voltage right now using Asus Probe and vcore voltage is only 1.06v and cpu is running at 4.0ghz. I just ran prime95 and the voltage automaticaly climbed to 1.46v so that is the voltage area you want to be using and not 1.175v if you are going to set it manually. I suggest you use auto voltage control for everything if your 1366 mb supports it like 1156 mb does.

p.s. About temps. What you see is never accurate and is more of just a guide. My bios temp gauge shows almost 10c higher temp than Asus Probe shows when in Win7. Which is correct? Probably neither. Correct temp is what your system can handle with proper cooling. That's why high performance cars have air scoops, it's not how hot the engine gets so much, it is how much heat it is designed to handle that matters and how well the cooling system is designed.
 
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when I first OC the CPU to 3.6 the voltage jumped to 1.46, which is way more than what intel recommends and many people here recommend. It's clear that I can run 3.6 stable at 1.175, so I was using much more voltage (and producing more heat) than I needed to, you probably are too.

I'm not going for straight up power, a 3.6 ghz i7 is more than I'll need for now and for a while, so instead I decided to see how cool I can run it at those speeds, I'm happy staying under 65c for 3.6. If I need more power down the road, I know my cpu can handle more.
 
OK, that's fine but as I said my normal vCore is only 1.06v and increases when I need it. That is better than running at higher voltage permanently as you have done by setting it manually. My CPU is still running at 4.0ghz stable at 1.06v when just doing most things on my computer. Only when I game will voltage increase. Look in the below article at the vCore voltage of the same cpu I have being stressed by prime95 and running at 4.2ghz. vCore is 1.512v which is more than my 1.46v and that site OC cpu all the time so I am not too worried about what Intel recommends so long as I don't start a fire. ;)

http://www.legionhardware.com/document.php?id=863&p=2
 
Hey, I've just discovered that by setting power management in Win7 from high speed to balanced that my cpu is now down clocking to 1.7ghz and lowering voltage during low cpu intensive task and then OC to 4.0ghz and raise voltage to 1.46 approx. during high cpu intensive tasks. This is pretty much what I want because now it only OC and use high voltage when I need it too. I tested it with the chess game in Win7 and during the CPUs turn to move its piece the speed of the CPU would go up to 4.0ghz and voltage would raise too, then when it was my turn the speed would drop down to 1.7ghz. I see the CPU using dynamic speeds all the time depending on what the task is, it will raisew and lower as needed. Do a task that is more intensive than web browsing but far less than a 3D game and it will raise CPU speed from 1.7ghz to only 2.2ghz etc. These i5/i7 are damn nifty and best CPU design I have ever seen in action. Kudos to Intel.
 
Yes, I know and actually have an E6850 and am typing this to you from that PC now which is auto down clocked to 2.0ghz from stock of 3.0ghz. But as far as I know the C2D did not auto manage voltages too. i5/i7 dynamically change voltages on both cpu and ram as needed too. That's why I can easily achieve 4.0ghz on my i5 750 without doing any voltage tweaking and could never get my E6850 above 3.4ghz.
 
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