W520 needs new thermal interface material. Paste, or pad?

[Surfrider]

edit: I should have researched better before asking this, 'cause look what I just found!: https://support.lenovo.com/us/en/documents/pd013117 I really don't have any excuse. Sorry. However, I am not going to delete the content of this post for the sake of future users with the same question.

I scored a free 2860QM, so it looks like the W520 is getting a transplant. Obviously, this will necessitate new thermal interface material, and I intend to order said TIM before disassembling my machine. Thus, my question: are the clearances between the mating surfaces of a W520's CPU and heatsink tight enough to use traditional thermal pastes? Or are they -- as I've seen with some other notebook manufacturers -- a bit big, thus requiring a "pad-type" to fill the gap?

FWIW, Thermal Grizzly Kryonaut has become my go-to paste, but I've been considering trying out the Coolabratory "Liquid Metalpad," and thought this machine might be a good guinea pig for a first-time experiment.

...And, by the way, anybody here happen to have experience with the latter? I've read numerous reviews, but I'm also interested in experiences from "real people."

Thanks.

[RealBlackStuff]

http://www.overclockershq.com/hardware- ... pages.html

[Surfrider]

Thank you. Yes, I've read a number of product reviews, and it seems that proper installation of this product is critical to its performance. However, when installed properly, most reviewers seem to get more positive results than the reviewer you've linked. Although, I was most interested in experiences from other forum users; I'm curious to see if they are consummate with "professional" reviews such as the link you provided.

Although, this is a moot point if the w520's CPU/heatsink can be coupled with traditional paste; I have Kryonaut on hand.

[RealBlackStuff]

Without batting an eyelid, or any second thoughts, I'll use AS5 every time...

[Cigarguy]

When properly applied, I don't find a lot of difference between pastes. Maybe 3-4 degrees. I just happen to have and use MX4 at the moment but yours seems perfectly fine. Again, proper cleaning and application of TIM is key.

[theterminator93]

There's a decent difference between good paste and cheap junk paste (or old, dried out paste). I did tests before and after re-pasting factory-original machines (T420 and W520):

A bit off-topic but when I upgraded from the i5-2540m (2.6 GHz/3.3 GHz turbo) to the i7-2640m (2.8 GHz/3.5 GHz turbo) I couldn't find my tube of Arctic Silver - so I used whatever I had that I could find - the "cheap white stuff" you're never supposed to use on anything you care about. I finally ordered new Arctic Silver and decided to do a temperature comparison before/after... with 4 Prime95 FFT/maximum heat threads running before AS5, TPFanControl instantly reported the highest figure it could on this system, which means temps exceeded this value (96°C (!!!)). With AS5 applied, temps are now 88°-89°C. Still a good 10° hotter than I'd like, but with at least a 7-8°C drop (probably closer to 10°-12° in reality) at least it's not as absurd as before. This is with the nVidia GPU shut down. Just goes to prove what we all already know - don't cheap out on thermal paste!

On the other hand... If I load up the NVS 4200 in Furmark with Prime95 still running, CPU temps again go above the 96°C max shown by TPFC and the GPU tops out at 82°. After terminating Furmark, it took about 60 seconds for the temps to start showing less than 96, eventually (after a several minutes) dropping back down under 90. My guess is CPU core temps during this got close to the maximum allowed temperature of 100. I can't imagine what temps would do with an extra 10W TDP thrown at the heatsink, even with good thermal paste. Thermal shutdowns at full load, my guess.

No Prime95 running, Furmark running, GPU climbs to 81° and a single full load thread on the CPU brings it to 88°.

This is all in a room with ambient temperatures of about 28°C (84°F).

I decided to replace the thermal paste with Arctic Silver 5 this evening, and while I was at it I decided to do some temperature measurements before/after the reapplication. The results speak for themselves. The heat sink and fan was already cleaned before either of these trials, so the only variable was the thermal paste.

Conditions:
CPU: Core i7-2860QM @ 2.5 GHz (3.6 GHz Turbo)
GPU: nVidia Quadro 2000M
Ambient temperature: 19-20C

Multi-threaded Prime95 CPU and FurMark GPU torture

Before AS5 application, I loaded 8 threads of Prime95 for small FFT testing (maximum heat). After a short time the CPU temperatures stabilized at 80C, with CPU-Z reporting the clock at 2.5 GHz, occasionally jumping to 2.6 GHz. TPFC fan speed was 64 (maximum) at roughly 4700 RPM. To load the GPU after this, I loaded FurMark. After five minutes the temperatures stabilized with the GPU at 89C (or 75C as reported by FurMark) and the CPU up at 96C, although the CPU had throttled back to 2.4 GHz, occasionally dropping to 2.3 GHz.

After the AS5 application, I repeated the same series of tests. 8 Prime95 threads for small FFT tests had the CPU stabilize at 72C - with the fan running at level 7 (3800 RPM) AND the clock rate was 2.6 GHz, occasionally dropping to 2.5 GHz. Five minutes after loading FurMark, the GPU ramped up to and stabilized at 91C (or 77C as reported by FurMark), although the CPU only reached a peak of 87 at a steady 2.5 GHz. Quite an improvement (at least in CPU temps)!!!

Single-threaded FurMark GPU torture

Five minutes after unloading the CPU of the Prime95 torture (only FurMark running), the CPU was mostly 3.3 GHz, occasionally jumping to 3.5 or peaking at 3.6, regardless of pre or post application. Temps before application were CPU - 81C, GPU - 71, after application CPU - 73C and GPU - 72.

Conclusions

Overall, the GPU temperatures didn't change enough to warrant any claim that the AS5 paste reapplication improved or worsened its temperatures. The reapplication of AS5 to the CPU, however, showed impressive results in both temperature and throttling. The multi-threaded tests ran 8C cooler while at a lower fan speed setting AND a higher clock frequency. Multi-threaded tests with a loaded GPU allowed the CPU to run 9C cooler without throttling back to less than full clock speed.

[hhhd1]

when the temp hit 96c on sandybridge, you should know that there is also throttling in performance.

while experimenting with heatsinks and made a bad move.., the temp was 96, but by i7 2620m 2.7ghz was actually running at below 2.0 ghz.

on topic:

the w520 may require thermal paste for the cpu & gpu , and thermal pads for the gpu ram, ... not a w520 owner myself, but many laptops run like this.

[ianb527]

I've had very good luck with the IC Diamond compound. As some have noticed, it can polish off markings on the tops of heat spreaders, but how often do you read these? I like it because it is completely non-conductive and non-capacitative and settles in pretty quickly (a couple of hours). If you use it, just make sure to do it right: one blob in the center of the die or heat spreader (an elongated one for a rectangular die) - and do not spread it. Squish the 2 halves together and let it sit for a couple of hours. It seems really viscous coming out of the syringe, but that is how it is.