Replacing the thermal interface material in a CPU package?

[GreenChile]

With Devil's Canyon, I'm of the opinion that unless you are psychologically hung-up on getting that last 100MHz out of your OC, it simply isn't worth your time/effort/expense.

For me personally, I would be psychologically hung-up on getting that last 100MHz if say, for example, I had a Devil's Canyon processor that could get to 4.9GHz without delidding.

Knowing my own personal "trigger points", I'm sure in that scenario I would likely delid my CPU just to get another 100MHz and make my rig turn in that nice satisfying "5GHz" overclock number.

But I wouldn't do it if I was already at 5GHz, not personally rewarding enough to do it just to hit 5.1GHz, or if my CPU was well south of the big 5.0 number, at say 4.6 or 4.7GHz. My brain would not be tickled pink just because I pushed my 4.7GHz chip to 4.8GHz with delidding, not worth the time and effort at that point.

But everyone has their own risk/reward profile and their own threshold trigger points when it comes to psychological reward in OC'ing. So I know my preferences are not likely to be representative of the larger audience.

An excellent description of what moves some people like us to venture into this realm. Personally I feel rewarded by reaching a level unattainable by other means, regardless of it's practicality in real world situations. It sometimes just feels good to know you've pushed it as far as you are capable of.

 

[BonzaiDuck]

With Devil's Canyon, I'm of the opinion that unless you are psychologically hung-up on getting that last 100MHz out of your OC, it simply isn't worth your time/effort/expense.

For me personally, I would be psychologically hung-up on getting that last 100MHz if say, for example, I had a Devil's Canyon processor that could get to 4.9GHz without delidding.

Knowing my own personal "trigger points", I'm sure in that scenario I would likely delid my CPU just to get another 100MHz and make my rig turn in that nice satisfying "5GHz" overclock number.

But I wouldn't do it if I was already at 5GHz, not personally rewarding enough to do it just to hit 5.1GHz, or if my CPU was well south of the big 5.0 number, at say 4.6 or 4.7GHz. My brain would not be tickled pink just because I pushed my 4.7GHz chip to 4.8GHz with delidding, not worth the time and effort at that point.

But everyone has their own risk/reward profile and their own threshold trigger points when it comes to psychological reward in OC'ing. So I know my preferences are not likely to be representative of the larger audience.

Well, they couldn't even get it to be reliably stable at 4.7. The V-increases they gave it from 4.4 to 4.6 appear to be regular. Even the temperatures seem reasonable, although you might exclude that for 4.6. You might know better, but I can't see how -- say -- a 20C reduction in temperature is suddenly going to find a voltage to bridge that gap between 4.6 and 4.7.

It seems to me that 4.6 is showing the "elbow" of an exponential swing in voltage required for that step up to 4.7. I mean -- suddenly -- it takes 0.15V just to reach a point where you can at least test it? Why would it be much different at 10 or 20C lower?

Even if a cooler chip could make that difference, you'd think to be "on the edge of the envelope" -- at the very limit.

 

[Tristor]

Another point of view, which is why I delidded for my relatively "mediocre" 24/7 OC of 4.4GHz, is that delidding allowed me to drop temps far enough to also drop voltages. For me, it was more about longevity and stability. The cooler the chip runs at load, the better, period. It did have the nice side effect of allowing me a lot more OC headroom for benching, but my 24/7 OC pre-delid/post-delid did not change, but my voltage did drop from 1.325vCore to 1.275vCore, which is not insignificant, and my peak load temp dropped by 19C (combination of voltage + delid), which is also not insignificant.

As much as I would have loved to chase the 5GHz number, this chip just couldn't do it, and I didn't have the fundage at the time to "trade up" by selling this off and buying another.

 

[BonzaiDuck]

Another point of view, which is why I delidded for my relatively "mediocre" 24/7 OC of 4.4GHz, is that delidding allowed me to drop temps far enough to also drop voltages. For me, it was more about longevity and stability. The cooler the chip runs at load, the better, period. It did have the nice side effect of allowing me a lot more OC headroom for benching, but my 24/7 OC pre-delid/post-delid did not change, but my voltage did drop from 1.325vCore to 1.275vCore, which is not insignificant, and my peak load temp dropped by 19C (combination of voltage + delid), which is also not insignificant.

As much as I would have loved to chase the 5GHz number, this chip just couldn't do it, and I didn't have the fundage at the time to "trade up" by selling this off and buying another.

Actually, you're pointing out something I'd failed to consider in my posts so far. There is a vicious cycle between temperature and voltage as temperatures rise. Lowering the CPU temperature may avoid this. On the other hand, reducing temperature may not capture much in voltage gains that apply to speed.

IDontCare can speak more to this than I can. At this point -- I'm "just an observer." It's interesting that the delidding got you a 50 mV voltage improvement at the same speed setting.

 

[Idontcare]

Actually, you're pointing out something I'd failed to consider in my posts so far. There is a vicious cycle between temperature and voltage as temperatures rise. Lowering the CPU temperature may avoid this. On the other hand, reducing temperature may not capture much in voltage gains that apply to speed.

IDontCare can speak more to this than I can. At this point -- I'm "just an observer." It's interesting that the delidding got you a 50 mV voltage improvement at the same speed setting.

It depends on the CPU, obviously, but in my case with an Ivy Bridge 3770K at 4.7GHz I saw a ~23C temperature reduction afford me a 37mV drop in required Vcc for the same level of stability.

Both the reduction in temperature and reduction in operating voltage for a given clockspeed (the so-called shmoo plot) definitely all go towards increasing the longevity of the OC'ed CPU, that is true.

 

[BonzaiDuck]

It depends on the CPU, obviously, but in my case with an Ivy Bridge 3770K at 4.7GHz I saw a ~23C temperature reduction afford me a 37mV drop in required Vcc for the same level of stability.

Both the reduction in temperature and reduction in operating voltage for a given clockspeed (the so-called shmoo plot) definitely all go towards increasing the longevity of the OC'ed CPU, that is true.

Yes, that was the table of results I remembered. We would all want lower temperatures for whatever clockspeed we find as an acceptable limit. Maybe both lower temperatures and lower volts might buy some stability at a higher speed, but it often seems that those limits can't be changed much.

I'm still vacillating between building a Devils Canyon system next year versus an E system. There's not much of a choice for delidding the 5930K. It would seem like a worthwhile pursuit to delid the DC processor, if that turns out to be the choice. And probably a less precarious matter of fitting a water-block to it instead of a heatpipe.