Overclock of i7 920 @ 3.6 GHz = 95 degrees?!

[aln688]

I've been overclocking my i7 920 CPU (C0) to 3.6 GHz using a CPU Ratio of 16 and BCLK of 200. When running LinX 20 passes and looking at Real Temp 3.00, my CPU's highest temp reached 95 degrees! Obviously this is too high, but why? If I overclock to 3.4 the highest is 86 degrees and stock 2.6 is 75.

I'm running with a P6T Deluxe V2 with 12GB of Corsair Dominator C8 RAM, Noctua SE1366 U12P (using a single Scythe SFF21G fan), Scythe G fan at the back and front, with an ATI 4870X2 installed. My voltages are: CPU Voltage 1.275, QPI/DRAM Voltage 1.275 and DRAM Voltage is 1.6.

I'm quite sure I didn't apply too much Noctua thermal compound, I was careful to put on a thin layer, and the fans are running full speed. When at 3.6 GHz I touched the Noctua heatsink, it was running warm to hot. Just wondered why I can't reach 3.6? Yet if I Google people can reach that but at around 70 degrees.

Thanks.

 

[Blitz KriegeR]

First, I'd say use a different program (I like Coretemp, or even OCCT default temp monitor is pretty accurate on my board) to verify your temps. Check your loads and your idles. What you're looking for is 1) check it's not a fluke and 2) are your temps high all the time, even at idle, or is there a massive differential between idle and load?

Next, I'd suggest reducing all voltages and frequencies to stock and re-measure those temps. This should help you figure out if it is your OC, or your HSF mounting causing the issue. (IE, are your stock temps significantly higher than the community average too?)

If you find that your temps are abnormally high in all the above mentioned trials, I'd say go ahead and reseat your HSF using the double-line method for applying TIM. (This involves drawing two very lean lines of TIM about 1/3 of the way in from the top and bottom of your CPU, making sure the lines are perpendicular to the processor cores. I'm not 100% of how this looks on an i7, but I think it would mean drawing the lines across the cpu the long way. Then plant your HSF on top, twist it ever so slightly to help spread/bond the compound, then mount down the HSF)

If on the other hand you find that your temps are closer to average when you reduce all voltages/frequencies to normal, then I'd say it's your OC, but reseating wouldn't hurt either way.

Oh and don't forgot LinX is like an oven, it puts your CPU under way more stress than anything you would do to it in your normal day-to-day. Standard OCCT or P95 temps are closer to what you will actually be running at; and even those are a worst case scenario.

Hope this helps some, get back to us with your results!

Cheers

 

[aln688]

Thanks. I did try setting all the defaults for voltages, etc. in the BIOS, setting the CPU Ratio to Auto and the BCLK (similar to FSB). My idle temperatures, again using Real Temp (downloading OCCT as I type this) are here:

Idle temperatures at Stock GHz

Load temperatures at Stock GHz

Core i7 920 with Noctua NT-H1

I'll let you know what OCCT reports.

If LinX pushes my CPU to temperatures that high, should I even be worried about this temperature on day to day use? Granted, wouldn't games push the CPU close to the stress LinX produces?

Thanks again.

 

[Blitz KriegeR]

40c idle at stock voltage is pretty high, and at 1.6Ghz? So you're looking at 40c idle WITH C1E (Intel's power/heat saving "enhanced halt state") is pretty high imo. Folks around the forums are getting about 45c idle with stock Intel HSF on a i7 920, so with your aftermarket I'd expect better. From what I've read most aftermarket solutions are in the 30-40 range, with Intel stock cooling at 40+. Listening to folks with my HSF (Thermalright Ultra 120-Extreme), they are getting about 30-35c idle.

Depending on what your airflow/room temp is like, you could be in an average temp range. IE, little to no airflow in the case or 100F room temps would make that sound normal. If however, you have good airflow/ventilation, and more like 75F room temps, I'd expect lower temps.

I'd go ahead and reseat my HSF and test again, if for nothing else just to collect some more data.

I don't know how comfortable you are with fooling around in your PC, but depending on your airflow situation I'd try improving that a little too. I'm always sticking my hand into my case checking airflow in important areas, just to probe around and make sure all is well.

Oh and it appears I confused OCCT's "CPU: LINPACK" test with "LinX". Didn't realize they were two different things.
For day-to-day worst case temps; ones that I'd worry about use OCCT's "CPU: OCCT" test, or Prime95.
For temps that are the absolute worst your CPU could ever get, what some consider above consideration because almost no normal activity can reproduce them, use OCCT's "CPU: LINPACK" or Intel Burn Test.

EDIT: Looking at your realtemp max readings; If you are hitting 79c load on stock voltage/frequency I'd be sure that *something* is not operating anywhere near peak efficiency. Ditto on the Airflow/Ventilation/Reseat HSF comments.

 

[imported_Shaq]

Your temps seem high at 3.6 with Linpack. I get about 83C max in Linpack at 3.8 (4.0 with turbo). Normal full loads are 65C max and generally under 60C. This is with Coretemp and HT off. Do you have Hyperthreading enabled? That adds about 10-15C to your temp and that would explain why it is so hot. If your rig is mostly for gaming then hyperthreading won't make them faster except for a couple of games. It just adds heat and compatibility issues.

 

[Serradifalco]

Originally posted by: aln688
I've been overclocking my i7 920 CPU (C0) to 3.6 GHz using a CPU Ratio of 16 and BCLK of 200. When running LinX 20 passes and looking at Real Temp 3.00, my CPU's highest temp reached 95 degrees! Obviously this is too high, but why? If I overclock to 3.4 the highest is 86 degrees and stock 2.6 is 75.

I'm running with a P6T Deluxe V2 with 12GB of Corsair Dominator C8 RAM, Noctua SE1366 U12P (using a single Scythe SFF21G fan), Scythe G fan at the back and front, with an ATI 4870X2 installed. My voltages are: CPU Voltage 1.275, QPI/DRAM Voltage 1.275 and DRAM Voltage is 1.6.

I'm quite sure I didn't apply too much Noctua thermal compound, I was careful to put on a thin layer, and the fans are running full speed. When at 3.6 GHz I touched the Noctua heatsink, it was running warm to hot. Just wondered why I can't reach 3.6? Yet if I Google people can reach that but at around 70 degrees.

Thanks.

Is your QPI link set to auto?

 

[C0bra1]

Judging by the picture I think you have too much Noctua thermal compound on the cpu. I have the same cooler and put a 4mm dab of the thermal compound down in the center of the cpu and I am getting load temps after running prime 95 for 35 minutes of 73 - 76. I am running at 3.6ghz (19x multiplier bclk 193, vcore 1.25, QPI auto).

i7 920 D0
Noctua SE1366 NH-U12P
Gigabyte EX58 UD5

 

[Soccerman06]

With stock fan and oced to 3.6ghz, I sit at 39C at the highest idling. God I really need to put my PM on.

 

[sizzip]

Hey C0bra, are you running with HT on or off? Also, what are your idle temps? Can you please post both idle and load temps of each core, i.e. 76-74-74-73, etc? I'm running practically the same setup as you (incl D0) and I wanna make sure I'm getting decent values. Lastly, what batch num is your d0? Thanks man!

 

[Schmide]

Originally posted by: C0bra1
Judging by the picture I think you have too much Noctua thermal compound on the cpu. I have the same cooler and put a 4mm dab of the thermal compound down in the center of the cpu and I am getting load temps after running prime 95 for 35 minutes of 73 - 76. I am running at 3.6ghz (19x multiplier bclk 193, vcore 1.25, QPI auto).

i7 920 D0
Noctua SE1366 NH-U12P
Gigabyte EX58 UD5

:thumbsup::thumbsup: think grain of rice or BB

 

[Thor86]

Do you have Hyperthreading enabled? That adds about 10-15C to your temp and that would explain why it is so hot. If your rig is mostly for gaming then hyperthreading won't make them faster except for a couple of games.

+1

 

[aln688]

Well I tried another run, this time using LinX at 9:30 AM in the morning here, this time I get 77 degrees, still at 3.6 GHz, the ambient is 75F (although the room feels cooler than that). I'm wondering if I should bother re-applying the compound to get it as "lean" as possible, hoping to see a lower temperature. (HT is currently on).

 

[aln688]

Originally posted by: C0bra1
Judging by the picture I think you have too much Noctua thermal compound on the cpu. I have the same cooler and put a 4mm dab of the thermal compound down in the center of the cpu and I am getting load temps after running prime 95 for 35 minutes of 73 - 76. I am running at 3.6ghz (19x multiplier bclk 193, vcore 1.25, QPI auto).

i7 920 D0
Noctua SE1366 NH-U12P
Gigabyte EX58 UD5

Well I re-seated the heatsink, applied a line method of compound to the CPU (explain later), and now with my Scythe SFF21G fan I'm getting a maximum of 77 degrees F.

I did try the 4mm blob method on my Noctua heatsink and Intel CPU, problem was after expirementing, the heatsink tended to squash the blob into an elongated egg shape, likely due to the way the heatsink is attached, lining up the screw at one end, then the other, and also the Noctua heatsink having fine arc'd lines on it. I ended up with a line of compound, 1/3 from the top of the CPU, 1/3 from the bottom, this seems to end up with an even circle of compound.