how low can vcore get and still be stable (q9550 @ 3.4)

[x3mgamer]

hi comrades,

this is my setup:

ANTEC 12000 case
MB ASUS P5Q Deluxe
Core 2 Quad Q9550
Radeon HD4870x2
Corsair Dominator 1066, (4x2)
PC Power & Cooling 750W
OCZ Vendetta 2


ive clocked my 2.83 quad to 3.4, what im trying to do now is lower the vcore to see how far down it goes while keeping stability

now the original clock was setup like this:

Vcore =1.2000, fsb = 400, multi = 8.5, Vdimm = 2.1, DIMM =1066



everest idle: mobo 39 degrees, cpu =31, core0 =51, core1 =48, core2 =45, core3 =45

speedfan idle: a degree higher than everest

realtemp idle: core0 =46 , core1 = 42, core2 =39, core3 = 39,

VID 1.2375, minimum hottest core 46, maximum 49

CPU-Z: CPU revision C1, Vcore 1.184, ddr frequency 533.3, fsb:dram = 3:4, timings 5-5-5-15-2T


starting prime95 64 bit version multiple cores (4+)(small fft test):

everest mobo 40, cpu 58, core0= 70, core1 = 67, core2 = 73, core3 = 72

coretemp: 0=71, 1=68, 2=72, 3=72

real temp: 66, 63, 68, 68, minimum hottest core 45, maximum 67


everest and core temp show some cores go to 73 degrees, is that too much temp for 24/7 work?

cpu temp during full load 60-61 (everest & speedfan)

after an hour of prime stress test the temp lowered a bit (55-57 cpu, 67-69 cores)


a day later...

lowered Vcore to 1.18125, temps fell to 55 max for cpu, cores maxed at 69 (everest)

real temp says: 62 60 64 64

minimum temps 61 60 61 63
maximum temps 63 60 65 65

how far do u think i can lower Vcore and still keep it stable at this 3.4 clock?

 

[V3NOM]

no idea. drop it one increment at a time and prime/orthos it.

 

[x3mgamer]

no idea. drop it one increment at a time and prime/orthos it.

is there any danger involved in droping it at that clock or any other for that matter?

how far do u think this cpu can go safe temp wise for 24/7 use?

 

[x3mgamer]

update:

dropped vcore to 1.16875, cpu-z is showing 1.152 @ idle, 1.168 @ load

cpu temp is still 55 @ load and why is it still 55? shouldnt the temp drop with dropping vcore, maybe the psu is compensating for lower voltage with more current? shouldnt i be getting bsod at some point, its still a 3.4 clock and 1.16875 doesnt look like enough voltage for that clock, or am i mistaken?

 

[outlw6669]

Your temps are fine.
As long as they do not go over 75c you will have no issues.
Keep in mind, when you are stress testing, there is an artificially high load on your CPU.
Under normal usage, you should never strain your CPU that much and, therefor, your temps will be lower.

To get the lowest stable voltage, drop you voltage in one step increments testing with prime95 between each drop. When you get to low, one of your cores will start failing testing. At that point, raise your voltage two settings and call it stable. Lowering your voltage below stock will never harm your CPU. It should allow it to run a bit cooler and draw less power.

 

[x3mgamer]

thank u outlw, i just came to a wall by dropping vcore, at 1.13125 prime fails and computer restarts, im currently priming with vcore set to 1.13750, so far so good with cpu temp at 53 and real temp cores @ 61 58 60 60, if i can run this cpu at 3.4 gigs @ 1.13750 voltage stable, do i have any chance of running it @ 3.8 gig at stock voltages say 1.2?

 

[Zorg]

According to Comps Core 2 Quad and Duo Temperature Guide a Tjunction of 75C is hot, 70C is warm and 65C is safe. If you approach 70C you would need to do the calibrations for Tcase to Tjunction to ensure that the Tcase max of 71C was not exceeded. I would recommend staying below a Tjunction of 70C and preferably below 65C.

 

[outlw6669]

If you have your chip stable at 3.4Ghz with only 1.1375v you may just reach 3.8Ghz with only 1.2v. The only way to know for sure it to give it a try. If it is not 100% stable, you still have some room to bump the voltage. 1.3v or a bit higher will still be safe for your chip, assuming you can keep the temps in check. From the looks of it, you have a very good chip.

 

[x3mgamer]

ok, 3.825 ,fsb = 450 @ 1.2 V gave me bsod so i bumped it up to 1.25 V and now its priming fine with cpu temp @ 68 and cores @ 79 76 85 87 (everest) and max cores 81 72 81 83 (core temp), what about cores being so high? is it ok as long as cpu temp isnt going over 75 or should i lower the fsb and vcore to avoid damaging cpu?

 

[outlw6669]

Well, it is an excellent overclock with such low voltage.
Unfortunately, it seems your cooling solution is not quite up to the task.
You need to keep your core temp at or below 75c for every core or you risk damaging your CPU.
For the moment, I would recommend lowering the speed and voltage until you are able to upgrade you cooling. With such a good chip, I would highly recommend putting it on watter and seeing how far you can take it with 1.4v....

 

[x3mgamer]

what about 1.4 V being outside of intel 0.8-1.3625 specs? my friend managed to push q9550 to 4.2 gigs with water but im not sure if he went that far with voltage

 

[outlw6669]

As long as it is kept cool, 1.4v should be safe for your chip.
As you are stable at 3.8Ghz with only 1.25v, I believe you would have no issues running at 4.2Ghz or higher with 1.3625v or less if you can keep the temps in check...

 

[x3mgamer]

excellent stuff outlw!

im back to 3.4 @ 1.1375 till i get some water, everest is reporting 41 degrees while priming, whats the safe range for mobo temp wise?

 

[outlw6669]

According to the Intel Spec Sheet, the P45 Nb is rated to a maximum of 103c.
As the P45 is based off a 65nm process and runs fairly cool, I doubt you will have any issues with it overheating.

 

[x3mgamer]

hi again, my overclocking soul is restless so ive decided to push the fokker again, as i type this the prime is running for almost 3 hours stable at 3.6 gig fsb 425, vcore 1.18750 and memory @ 1066

cpu temp reported by everest is 53-54, mobo stays at 29

core temps go from 65-70


real temp reports minimum temps at 59 56 57 56

maximum at 63 60 65 65

its incredible even though this chip is C1 revision it manages to keep this overclock stable at only 1.18750 vcore

 

[alwaysoc0nfused]

lucky you, I have a q9550 on 780i, currently overclocked to 3.4 at 1.275. anything lower Intel Burn Test gives me BSOD. My goal is to get to 3.6ghz.

Lemme ask you, did you have to up the FSB volts?

 

[x3mgamer]

u mean gtl voltages? i was running this cpu at 3.8 the other day with OCZ Vendetta 2 but thew temps of the cores reach and pass 80

do i need some guide for raising or lowering gtl voltages, how can i set those up and not fry anything? i ask coz id like to further lower my vcore

also whats that about PLL voltages, from what i understand theyre tied to sb so wont raising pll result in need to tweak sb voltage too?

 

[alwaysoc0nfused]

Im talking about the voltage setting right under the cpu setting in bios, i think its called the vtt (i have a 780i board).



also this might help give you an idea about ur temps. my temps are:

idle: 29c
load (IBT, OCCT, Prime): 57c max

 

[x3mgamer]

ya ur cpu temp under load is 57c max but that doesnt mean ur core temps rnt going over 65 or maybe even 70, what r ur core temps?

i havent touched vtt voltage yet, i still have to try gtl voltages first

 

[alwaysoc0nfused]

sorry i meant core temps. they dont go over 57c. thats the highest any one of them has ever gone.

 

[x3mgamer]

wow thats what im aiming for, at 400 fsb, vcore of 1.14375, and 3.4 gigs my core temps go to 61 tops in everest, 58 in real temp, do u have water cooling or what coz i cant see how can u have such low temps at 3.4 clock

 

[x3mgamer]

do u guys think id lower my core temps by lowering multi to 8 and raising fsb to 450 and getting that 3.6 clock that way instead ?

 

[alwaysoc0nfused]

I use the tuniq 120 tower. Ill admit the first time I put it on with the thermal stuff my temps were like yours if not higher at stock. Then i took everything off and i spend like 30 mins carefully appling the grease. I did it evenly and carefully and then i mounted the tuniq 120. I loaded up the comp ran tests, at stock core idle was at 25c, 100% load was less than 45c.

 

[x3mgamer]

im waiting for my xigmatek crossbow or tr s775 bolt-thru kit and then ill apply thermals again

 

[x3mgamer]

is it true u need to set pcie frequency to 101 otherwise itll be auto raised with fsb and shyt?