X79A-GD65 8D DrMOS overheatiing

Question

Hi
So I managed to get my setup working properly on BIOS 1.6. It is as follows:
3930K C2 (cooled with Corsair H100)
X79A-GD65 8D
4x4Gb gSkill 1866 RAM
MSI GTX 580 Twin Frozr II (cooled by a corsair H80)
Corsair GS700 PSU
Aerocool Xpredator Case
I made this setup mainly to render a video sequence with Maya 2012. The takes of this video are for an Airplane dogfighting game we're developing at my company, so the video is full of clouds and its pretty heavy on rendering. So I overclocked the 3930K to 4,6 and it were doing pretty fine until last night when the mobo turned off without any BSODs or any warning.
The processors were all using 100% of them during almost two days without a stop before they shut down... The highest temp on the hotest core were 73 Cº and the wattage consuption measured by CoreTemp were around 173W. By that time the Vcore was on 1.360mv and clocked on 4,6Ghz (100BCLK x 46), with every other voltage set on the mobo's default.
My DrMOS alarm were on so I imagined it reached the 130º and switched off. I didn't knew it managed to reach theses temps so easily though.
On my OC setting I messed ONLY with core voltage and PLL voltage, so everything else I lowered on the below description was from the default setting.
I'm trying many OC settings to lower DrMOS temps, as processor temps and voltages are OK. I don't know which voltages affect DrMOS at most, so I tryed to lower Agent Voltage first.
Got it from 1.224mv default to 1.100mv and worked nice, but DrMOS alarm was still getting on and after the 9th pass of Prime 95 it turned off with processors at 75º and 195W.
I finaly got it from shutting down when I started lowering Vcore and raising PLL. It achieved almost the same temps, and the alarm still got on, but it didn't switched off anymore.
I got 4,6Ghz (100 BCLK x 46) at 1.340mv with 1.840mv PLL, 1.100mv System Agent and all other voltages set on stock.
But as I live in Brazil and its pretty hot the temps here on this time of the year (ambient in an afternoon is about 27-30 Cº), I was wondering about the DrMOS Alarm that was still on on the 2nd pass of Prime 95...
Later I will try to lower Vcore even more and raise PLL a bit to see if it helps.
My question are:
1- Should I try to reaply thermal Paste to the DrMOS chips to the mobo heatsink? I have an MX-4 here.
2- Which voltage should I try to mess to lower the DrMOS Temps?
3- There is anyway on this mobo to change the TDP of the CPU? I didn't found this on BIOS... Only found option to enhance its OCP which apparently doesn't helps much...
Sorry for the long post. I only tryed to enlighten the situation the most with my poor english.
I apreciate any help.
Thank you very much

Answer 1

Quote from: HU16E on 15-April-12, 14:37:28
Fairly sure it is gray thermal tape being used. One simple test is to press down on the heatsink with a pencil erasor and wait a few seconds and see if the temperature starts to drop. If it does, you have a contact or alignment problem. Out of habit, before I mount the mainboard in the case, all the screws are checked for tightness on the backside of the mainboard.
I'll run Prime95 after the current render session ends and check that when the Alarm led apears.
Replace the gray thermal tape with the MX-4 would be a good idea?? I mean, if theres a tape, after removing it, wouldn't it leave a tiny gap space betwin the heatsink and the chips? To use the Paste they should be touching each other, right? or is it possible to apply the paste and tighten the screws to eliminate the gap? I did it once on my old mobo which I had one spare to try out, but I confess I'm pretty afraid of doing something wrong with this one...
I think that lowering Vcore and stabilizing the clock raising PLL might be working fine because it have been on a rendering session for almost 6 hours now and no alarm led so far. But I'm pretty sure that if it was Prime 95 the led would turn on in about 2 minutes... As the rendering despite using 100% processor power only consumes around 170W with this OC settings, and Prime 95 consumes around 195W. After the render is finished I'll mess a little bit more with that and check the temps and maybe try for 4.7Ghz with 24/7 voltages.
This processor is damm good! I'm geting pretty good clocks with very low voltages! If it weren't for these DrMOS geting this hot I think 5.0Ghz could be achieved or 4,8 - 4,9Ghz with 24/7 voltages...