i7 940XM Temps across cores different.

Hi
Just looking for some opinion to the above issue .
On stressing the cpu i have 1 core thats constantly 8-10 deg C cooler than the rest .
I used Intel Processor Diagnostic Utility and stressed the cpu to 100% on all cores for 5 minutes .
My last stress test the highest temp was Core #2 @ 80.0 C
Core #0 and 3 were around 75.0 C but Core #1 was 70.0 C

Over all im happy with the temps on the 940xm topping out at 80 C but why is there 10 C difference ? Is this needing a repaste as its been 4 months or so since it was done and wasnt like this in the begining.
Heatsyncs have been blasted out with compressed air , or is this uneven pressure on the cpu from the heatsync or possibly a warped heatsync ?
Im kind of hoping not to strip this down again but if needs must

 

Core Parking and Turbo will give your core different temperatures, it`s normal.

John.

 

Even if all cores were stressed to 100% for 10 minutes using Intel Processor Diagnostic Utility ?

 

Wow ..... guess I'd stand a better chance asking someone walking by the house .

 

Don't lose hope, I'm also waiting for a reply, since I've got the same problem.

Here's what I found out - it may be a problem with the temperature sensors, they're not perfect. And I think that's a pretty plausible explanation, since my core #2 was always a few (up to about 5) degrees hotter than the rest, and core #3 was a bit cooler. I thought I just screwed up when applying thermal grease. Yesterday, I installed a new CPU cooler and, of course, reapplied thermal grease. I may have botched it again, because I pretty much had no idea what I was doing, but that's not the point. Right now, my temperatures are way better than before, but still those two cores are respectively hotter and cooler. There's a pretty slim chance that I applied the thermal grease wrong in exactly the same way, especially since I used a different methos this time, so I think that it's the sensor's fault and I'm not worrying too much about it. And yes, I'm talking about a desktop computer here, not a notebook, but I think the principle is the same and Intel doesn't make different sensors for notebooks and desktops.

But, of course, I'm not 100% sure that this is the case, so I'm also waiting for someone more experienced to answer.

 

Thanks for your input ... when i first put this processor in there was only a few degrees difference even using prime 95 to stress the cpu to 100% they all seemed within a degree or two .. but it seems to have slowly gotten worse over the last few weeks to i now have 1 core running up to 10 degrees C cooler .
I guess im just going to have to strip it down again and re-apply the MX4 paste .

 

Hi there, I had some major temp differences with my i7-940xm in my GX660R, have reapplied fresh paste number of times, and it never helped out too much, difference could be 5-8 degree between some sensors, now I went and got best paste that can be got Phobya HeGrease Extreme - ebay link, german seller,fast delivery - (1985.71 EUR/KG) Phobya HeGrease Extreme 3.5g | eBay

well now my temps are max 2-3 degrees between cores and on heavy stress these temps grow alot slower compared to MX4, and meaning temps raising slower on same stress test means heat transfer is better, so I advice to get this and try it out, well worth In my opinion.

Thermal conductivity benchmark and review page for number of thermal greases:

Skinnee Labs | Taking the guess work out of PC Cooling

and straight to charts:
2011 Thermal Compound Roundup – Results Compilation | Skinnee Labs

BR