Clevo P370SM/Sager NP9380 Cooling Overhaul

Updates
27th July 2014: Swapped 880M heatsink for 8970M heatsink. 8970M heatsink better but only under more strenuous conditions, otherwise identical.
30th July 2014: Cut away some metal in the U3 cooler to increase airflow, another major drop in temps.


Overview

This thread is essentially a compilation of the various mods I performed on my P370SM to improve its cooling capabilities over the period of several months. Most of these have been documented in detail, but the actual posts/threads are scattered all over the forums, some even in the Alienware section. I am now piecing everything together into one central thread for everyone's benefit. Most of these mods should work equally well for the P370EM, P375SM, and P37xSM-A. However, I am confident that a few will be universally applicable to other laptops (Clevo or otherwise).

The initial impetus behind all this modding was increased component temperatures due to the summer heat. As there is no AC in my room, the ambient temperature is 24°C (75°F) even at night, and on hot days it rises to an uncomfortable 30°C (86°F)! I initially simply wanted my P370SM to never exceed 80°C on any of the components during summer gaming. But as I kept modding and temperatures kept dropping, eventually it became an obsession to see just how far I could drop the temperatures.

I am still not quite finished with modding at this point, so this post may be updated from time to time as I complete and validate any new mods.

Before I begin, I will acknowledge a few key people that motivated or helped me along the way to keep all this modding going. They were the brains behind a lot of these mods, and I was simply the technician.

- deadsmiley for discovering the TechInferno mod, as well as his own mod that helped me get the ball rolling, and for providing very helpful tips and pictures when it came to lapping the heatsink

- sl44n3sh at TechInferno for various mods

- Gerik at OCN for the awesome Notepal U3 fan mod

- Khenglish at TechInferno for various pointers and tips, and especially for pointing me to the 8970M heatsink

The P370SM: A Brief Introduction

The P370SM is the second iteration of Clevo's mobile SLI laptops (the first being P370EM). Compared to the P370EM, the P370SM made several major changes to the cooling system, among them the omission of the third heatpipe from the CPU heatsink that shared the slave GPU fan, beefier 6mm heatpipes for the master GPU (instead of 4mm in the P370EM), and a one-piece construction for the slave GPU heatsink that now sat flush with the fan and had no issues with air leakage due to unnecessary voids. While these improvements are welcomed, I feel that Clevo made a number of questionable design decisions, and the end result is that the cooling is still not as good as what it should be. Thus the task is placed upon the end user to rectify some of these issues and unleash the full potential of the P370SM.

For reference these are the main specs of my P370SM:
-4900MQ
-780M SLI
-2x8GB 2133MHz ram
-1TB 840 Evo boot + 500GB 840 Evo data
-Running Prema's BIOS mod v2 for the P370SM

Everything was run bone stock (clockspeed, vBIOS) for all testing. Liquid Ultra was used on the CPU. MX-4 and Gelid GC Extreme were used on the GPUs.

And without further ado...

The Mods: Part I

External Cooler Mod

Let me refer you to Gerik's thread on OCN where he combines 3x 120mm Rosewell case fans with a Notepal U3 cooler.

Since Gerik has an excellent guide up, I won't repeat myself here. I will just say that my fan controller had a dead DC jack on arrival, which made me think the whole thing was DOA. However I was able to get it to work using an AC to Molex adapter that was meant for HDDs, and plugging into the Molex end of the fan controller. It's a bit cumbersome, but on the plus side I gain the ability to switch the fans on and off at will.

Spoiler

You see what I mean by cumbersome? Granted it doesn't look too bad in this picture because I hid all the fan wires LOL, but believe me when I say it's a handful (literally). The green light is the on/off switch from the AC adapter. In a way I'm thankful the DC jack died, otherwise I'd have no way of stopping the fans short of unplugging the entire thing.



The wires for the 3 120mm fans can be neatly routed through the back of the U3, and don't get in the way at all.

This is probably the easiest mod of them all, and for such a small amount of effort, I recorded a 5°C drop on the master GPU and 2°C drop on the slave GPU. Not bad at all.

UPDATE: I took Gerik's mod one step further and cut out some metal to improve airflow:


The results are quite nice, as you can see below after playing Watch Dogs for 30 minutes:


The CPU benefited the most with a 4C reduction in temps, while the master and slave 780Ms shaved off 2C and 3C respectively.

GPU Cooling Mods

Exhibit 1: Sealing unnecessary voids

Spoiler

I'm really not sure what it is with Clevo and voids, but here you go. The fix is to simply tape off the offending area of the fan with some foil tape. It takes literally less than 1 minute, and the result is a 1-2°C drop in temps when gaming.

Spoiler

The CPU heatsink also has a rather large gap between the fan and the fins, but in this case applying foil tape didn't make any difference, so I just left it be.

Spoiler

Exhibit 2: An improved heatsink
UPDATE: I changed the 880M heatsink to an 8970M heatsink following a tip by Khenglish.

When I was going through HTWingNut's review of the P377SM-A, I noticed that the 880M heatsink for the master GPU in the P377SM-A seems to have slightly improved compared to the 780M heatsink: it is now a one-piece construction instead of separate core+vRAM heatsinks, so one doesn't have to worry about misalignment between the two parts obstructing airflow and, perhaps more importantly, fin area seems to have increased. As a bonus, the 880M heatsink includes a bit more foam padding on the fins to block off the atrocious void I mentioned in exhibit 1.

Spoiler

NOTE: The 880M heatsink has a row of missing fins that do not extend all the way back from the core heatpipes. Not sure if this was to cut cost, or to isolate the VRM heatpipe from the two core heatpipes.


The 8970M heatsink doesn't have this missing row of fins and has one giant radiator:


I measured the dimensions with a caliper and the two heatsink are virtually identical. In fact, I suspect the 880M heatsink may have been derived from the 8970M heatsink! The only difference between the 8970M and 880M heatsink is the placement and size of the thermal pads. All I did was switch the pads over and the 8970M heatsink fit like a charm. I threw in some Gelid GC Extreme paste and ran some tests:


Unigine Valley was run for 10 min using Extreme HD Preset, Watch Dogs was played for 30 minutes on Ultra + SMAA, Far Cry 3 was played using Ultra preset + HBAO + 2x MSAA and played for 3 hours.

Ignoring Far Cry 3 for a minute, you can see the heatsinks perform identically, with maybe the 8970M having a slight edge (although 0.3°C is hardly significant). But, as I correctly assumed, I had to push the cards harder to see a difference. After a 3 hour gaming session of Far Cry 3, peak temp dropped 3C, while average temp dropped 2C. Again not a significant improvement, but every little bit adds up in the end.

Because of better temps under heavy load, as well as the potential for better VRM cooling (see pages 3-4 in this thread), and not to mention the 8970M heatsink is cheaper, I'm recommending the 8970M heatsink over the 880M heatsink.

Text below only relevant to 880M heatsink, but I'm keeping it for reference

Spoiler

So does the 880M heatsink actually offer any improvement over the 780M heatsink? Yep it sure does. The following records the temperature taken at 1 minute intervals while running MSI Kombustor 3.0:

Spoiler

I was very happy to find that the 880M heatsink did indeed perform better than the 780M heatsink; not only was peak temperature reduced by 2°C, it also took longer to reach the peak temperature.

Exhibit 3: Opening up restrictive vents
Have you ever taken a moment to stare at the fan grilles on the bottom cover? I certainly have, and I've always wondered just how much the fans are being starved of air by these tiny vents. This is what the vents on the P370SM look like; for comparison this is what the bottom of the Alienware 18 looks like. See the difference? The baffling part is that Clevo clearly realizes the importance of non-restrictive vents, because the P570WM has some pretty awesome vents. So why the vents on the P370SM are the way they are I don't know.

The fix is easy enough if you know what you're doing: take a Dremel to the bottom cover and cut some holes.

Spoiler

And here's a bunch of close up shots:

Spoiler

Master GPU


CPU


Slave GPU

Spoiler

Master GPU


CPU


You may have noticed the CPU opening is slightly smaller and does not encumber the entire circumference of the fan. That's because there are some support structures (the black "fins" at each of the four corners) that get in the way, and I did not feel like cutting those out.

Slave GPU

Spoiler

By simply allowing the fans more air, I saw a 3-4°C drop in temps on both the master and slave GPU.

Exhibit 4: De-warping aka lapping the heatsink

I will admit to being completely ignorant to this issue until Khenglish at TechInferno pointed this out:

Now you know why the temps suck despite the strong fans. But as you will see towards the end of this long post, when all (or most) of the issues are rectified, the cooling system finally starts to tap into its full potential.

The fix for warped heatsink is both easy and hard: it involves lapping the heatsinks, or sanding down the uneven parts until you achieve an almost perfectly flat surface that has a mirror-like finish. The fix is very simple conceptually, but the execution can be rather difficult on a laptop heatsink. I started with the slave GPU heatsink as the contact plate had no "tabs" on 2 corners unlike the master GPU heatsink (see exhibit 2 for pictures), so the contact plate was completely flat, and easier to work on.

The materials I used:

Spoiler

I skipped both the 400 and 600 grit as I didn't want to take too much material off. The metal block to the far right is a 1-2-3 machinist block, which provided the flat surface I needed to sand down the heatsink.

So what I did was use the 3" side of the 1-2-3 block and cut a piece of sandpaper that was just slightly larger than the area of the contact plate on the heatsink.

Spoiler

For the actual lapping I pretty much just followed the guide from OverclockersClub that I linked to above. Every 3 complete rotations I washed off the copper shavings on the sandpaper, and reapplied dish soap to the heatsink. I went 800, 1000, 1500, and finally 2000 grit. I had 2500 grit sandpaper but quite frankly I was just too tired at the end and decided to call it a day. The entire lapping process took about 2 hours, and both my hands and wrists started giving out towards the end. You will need a lot of patience if you want to do it right, so make sure you're in the right frame of mind when doing this. This is NOT something you want to rush, as I can tell you from personal experience that I almost trashed my heatsink because I was rushing the first time through. Also, the actual process is very messy as copper containing water/foam will get everywhere, so either do this outside or near a sink, and make sure you wear nitrile gloves.

The end result does look quite stunning though: (note that this is actually a second lap; the first one was botched because I rushed so again DO NOT RUSH THE PROCESS)

From left to right: before lapping, 800 grit, 1000 grit, 1500 grit, 2000 grit


For 2 hours of my trouble, I shaved 3°C off the slave GPU while gaming. The rather modest drop is because my plate wasn't all that warped to begin with, as I know deadsmiley who had a rather warped plate experienced a drop of over 10°C. For the vast majority of you this may not be worth your trouble, but to a temperature obsessed enthusiast like me every °C counts, so I'm happy with the result.

Summary of Results for Part I
If you don't feel like reading the gigantic wall of text above (which I totally understand), then this single table of results is all you need to convince yourself that these mods really do work.

Below I have recorded the temperatures, both the absolute peak as well as the average after 30 minutes of playing Watch Dogs on Ultra with 2x SMAA.


Note that the cells highlighted in light blue are results from using Gelid GC Extreme paste. All other results were obtained using MX-4 paste. So as you can see even something as simple as changing to a different paste can drop the master 780M temp by 2C. Additionally, you may have noticed the slave GPU temperature went UP with the 8970M master GPU heatsink. This is because MX-4 has terrible durability, and after 30 hours of Far Cry 3, temps have already deteriorated even when playing a less demanding game like Watch Dogs.

What is remarkable though, is just how effective a cut out U3 with 3x 120mm fans is at cooling the P370SM. The CPU dropped 4C, the slave 780M dropped 6C, and the master 780M dropped about 8C! Compared to a "stock" P370SM with an 880M heatsink, temps have dropped 10C across the board. And all this in a room with an ambient temperature of at least 24°C, with the ambient temp usually hovering around 26-28°C during daytime.

Btw what I'm not showing here is just how effective the U3 cut out mod is when combined with a good thermal paste like ShinEtsu X23-7921-5. After an hour of Far Cry 3, my peak temps were down by 7C!. Previously the master 780M would go up to 77C, and the slave 780M ran at a rather hot 82C. Now the master tops out at 70C, and the slave doesn't edge past 74C. And all this in a 26C room. What a difference!

I can't wait to see what kinds of temperatures would be possible during winter, when ambient temp can drop to as low as 16°C if I don't turn on the heater. Perhaps I'll finally be able to play Crysis 3 with both GPUs under 60C LOL

 

The Mods: Part II

PCH Cooling Mod
In case you didn't know, the PCH chip is located under the keyboard in the P37xSM models. (see pics below)

Spoiler

As you can see, the PCH just quietly hides under the keyboard, with no access to air or ventilation of any sort. Because of this and the high summer heat, my PCH would idle at 62°C, and could go up to 83°C when gaming. Since the keyboard backplate is one big piece of aluminum, I figured why not bridge the gap between the PCH and the keyboard and use the keyboard as one gigantic heatsink.

So I used my caliper to measure the gap between the PCH die and the keyboard backplate, and it came in around 4.2mm. I figured 2x2.5mm thermal pads would do the job nicely:
(here I actually just used the stock square 2.5mm pads that go on the inductors from a spare 780M heatsink, they fit very nicely and the size was perfect)

Spoiler

Look at the nice impression the die makes in the stacked pads:

Spoiler

I didn't expect too much from this mod, since I'm stacking 2 thick, stock Clevo thermal pads, and the pressure isn't that high. But even with this rudimentary mod, the idle temp dropped by 7-8°C, and the temp maxed out at 73°C after an hour of playing Watch Dogs, representing a 10°C drop in load temps.

The keyboard did not feel any noticeably warmer, probably because the heat is concentrated between the "\" and "enter" keys. However I will say I don't know what the long term consequences for the keyboard would be, so do this at your own risk.

8/8/14 edit: I checked the Intel datasheet, and the TJmax for the HM87 PCH chip is 108°C.

CPU Cooling Mod
Remember the triple pipe CPU heatsink of the P370EM I mentioned earlier? Well turns out this fits in the P370SM just fine, and gives the CPU healthy temperature drop because of the extra cooling from the slave GPU fan. The problem is that all the extra heat from the CPU is 100% off-loaded to the slave GPU, which is completely unacceptable in gaming situations. I'm not going into any details here because this isn't really a worthwhile mod unless you're into hardcore CPU benching. In any case I wrote about my findings here, so all the details are there for you to see.

 

(Reserved)

 

Apparently I can't rep you again O_O. Anyway... with average temps like this, OCing becomes a welcome/healthy possibility again. Imagine if you were using liquid ultra too.

 

2 hours... Man that's some dedication! I couldn't do it man but awesome findings, thanks for putting it all together!

Sent from my HTC One_M8 using Tapatalk

 

Same here lol. I must spread more rep around first XD

 

Excellent work! I know it was a chore pulling all that together and of course there is always more to write about once you start.

I missed the PCH cooling mod somewhere along the line. Now I have something else to look into... ha!

 

Unfortunately I don't think the PCH cooling mod will work on the P1xx series, mainly because Clevo made a bonehead move and decided to add a piece of plastic over where the PCH chip is.

Although if I remember correctly Prema was able to cut out the plastic and put a piece of copper ramsink between the PCH and keyboard. It's in a thread over at TechInferno but probably best to PM him at this point.

 

Bleh...

10char

 

<del>Added a blurb about my warped 780M in the second post. If you're a P370SM owner please take a moment to make sure that your master 780M hasn't suffered the fate.</del>

Will make a thread about this since this is a serious issue.

 

My PCH idles at 77c. Is that bad?

 

It's a bit high but the danger zone is 100+C according to Meaker. Before my PCH mod it idled at about 65C, and with the mod it idles at 57C.

 

Ok, I finally had to google PCH. Basically, it's the South Bridge.

Everything You Need to Know About Chipsets | Hardware Secrets

 

I once saw my PCH hit 102 degrees. That never happened before aside from that one time, though it was scary to me. Basically, don't put a video to render in handbrake with high encoding profile, 4.1 x264 level, slow preset, start up Black Ops 2 and lock the game to 120fps while watching two livestreams on twitch at source quality in google chrome.
....
Yeah, I do... stuff... with my laptop. Lots of stuff. Sometimes at once. Usually at once. But that, don't do that. You'll fry your southbridge. I think.

 

It will go high, people have put little metal heatsinks on or padded them to a surface to cool them, a step to consider if you want to do really heavy I/O, for most users it should not be an issue.

 

@deadsmiley: If you really want to, you can cut away the plastic highlighted below to do the PCH mod:

 

Yo what the COW is that pictu--- oh, he doesn't have our model. Whoops. Still though, I can't wait to order some spare heatsinks and a backplate and get em working great.

 

I don't think it's causing any issues for me. Right now my issue is I am out of town on business and my new 330w power brick was delivered on Monday.

 

I would do the mods in this order:

1. Cut holes under fans
2. Install 120mm fans on U3 cooler
3. Replace master heatsink with 880M heatsink
4. Lap the heatsinks

Cutting holes and using 120mm fans already net 70% of the thermal benefit. The 880M heatsink helps the master GPU but doesn't do much else. Lapping can be hit or miss: if you have a crappy heatsink it'll actually provide the most benefit, but if your heatsink is already decent then it's really just to squeeze that one last bit of cooling performance out of your system. Speaking of which, I still need to find some time to lap the master heatsink, although with the temps I'm seeing I hardly have any motivation to do so.

 

I wasn't going to use the U3 cooler, actually. I was just going with raw mods, but everything I do will be done with spare parts so I don't ruin anything currently here. I'll store the extra parts somewhere in case I ever need to get anything replaced, though I probably will keep Liquid Ultra around as my primary paste if it works better (which I'm sure it will). I'll be doing that foil-tape fan mod asap though, even 1-2 degrees celcius cooler is leaps and bounds to me.

 

1 and 4 should be swapped dude. If the heatsink is warped everything else is secondary in my opinion.

Of course my GPU heatsink was pretty bad...

 

I agree if the heatsink is not quite right the rest wont mean much.

 

Yeah I was debating that, but lapping really isn't just someting you just jump into, and if you screw up you better have a spare heatsink lying around. The other mods are much more forgiving, and take a lot less time (and finesse). I decided to just add a note at the end to say what you guys basically said.

 

I think it's just the fear factor kicking in. I would have been hard pressed to make my GPU heatsink worse.

 

"Ah look at mah shiny new heatsink, isn't that mirror fin..."

*drops heatsink*

"[censored]"

 

Yours is so shiny all the girls want one on their finger!

 

The master GPU Heatsink from Clevo P370 looks exactly the same with the GTX880M Heatsink for P1xxSM.
Am I right?

I found a listing @ ebay (8970M with P370EM heatsink) to replace my dead 7970M
this is my best option since Clevo GTX680M price is even more expensive than GTX780M (and the 7xx series won't work either in P150EM)

Any help would be much appreciated.

- Gustav

 

Yes the master heatsink dimensions are used across the whole range of MXM machines.

 

I seem to recall the screw layout iwas slightly different for the master heatsink between the P1xx and P3xx series, particularly the #7 screw.

 

Ooh I thought it would be similar just like Meaker said.
Which one is the #7 screw? Is it the one nearest to the VRM area?

 

Yes it is. You can go to Prema's site and download the service manuals for P150EM and P370SM and compare the screenshots for the master GPU heatsink and see if they are different.

EDIT: I just looked closer and it does seem from the pictures screw #7 is more or less in the right place. So a P370EM heatsink may work.

 

Really, it looks the same to me, I have never swapped them so I may be wrong, but where do you measure that or hear of it?

 

I got thrown off by the tab with the 2 extraneous screw holes that don't need to be there

Yeah like I said I looked closer and it seems like it's in the right spot. Although if that's the case may as well opt for a 8970M heatsink for the P370SM, since it's a one-piece construction with one big radiator, but without the silly fin cutout for no reason on the 880M heatsink.

 

It's for the 377SM which had a slight indent there.

 

Well that's $90 down the drain

 

Nah, somewhere, somehow, someone will want the 8970M heatsink for their <S>8970M or 7970M</S> R9 M290X, then you can sell it back.

 

It's the fins closest to the fan that's missing though, is there a hidden indent somewhere there?

 

Closest to the fan? They are all equally close to it... I'm talking about the fins closest to the side edge of the machine.

 

yeah can't explain this with words, but pictures will help

This is what I meant by missing fins:



I see absolutely no good reason to leave out that row of fins (other than to cut cost)

 

Oh you mean the top does not go fully back? It could be cost/weight or potentially the VRM pipe is deliberately isolated from a section of the heatsink.

 

Hmm, since the 880M is pushed to its limits perhaps the VRMs do run hotter than the 780M, so isolating the VRM heatpipe might provide some thermal benefit (at the expense of the core)? Just theorizing here.

Btw received the 8970M heatsink today. Going by some rough eyeballing the dimensions seem to be pretty much the same as the 780M/880M heatsink, with the only difference being different pads. The 8970M heatsink has one gigantic radiator that doesn't leave out those fins like the 880M heatsink. Will do some testing later.

 

Well if the fins there would basically be cooling the vrms, heating up the air before it hits the fins that are connected to the core's pipes. So putting fins there could raise your core temp.

 

Well at least I'm on the mark for once lol

Although I'm curious if the increased fin area could counter what you described somewhat, so the end result is it breaks even and there is no net effect on the core but the VRMs run a bit cooler due to increased fin area

 

Not really since the thermal conductivity of the fins from one edge to the other is much less than the heatpipe sitting right on that side of the fins

By in large it would be cooling the vrms alone.

It's the same reason the heatpipe in the other style of combined units did not go all the way across for the VRM pipe. While I think there are ways to improve the design it's often not as obvious as people think.

 

Huh that's interesting. Now I'm curious whether the improvement in core temps I saw with the 880M heatsink is basically what you described -- decoupling of the VRM and core heatpipes.

Also I find it intriguing that Clevo chose a 2-piece design with the 780M heatsink (probably to minimize the heat exchange you described), while they stuck with the one-piece radiator with no cut out for the 8970M.

Well in any case if the 8970M heatsink maintains core temps I'll keep it, since I don't mind having the VRMs run a bit cooler

(btw @ 4mm VRM pads on the 8970M heatsink)

 

OK so I finally found some time to install and test the 8970M heatsink, and thankfully I did not see an increase in core temps. If anything, temps dropped by 2-3C under a heavy load. See the original post for more details. But I'm officially recommending the 8970M heatsink over the 880M heatsink. Ditch that stock 780M heatsink guys, it's <del>junk</del> inferior.

Btw, the 8970M uses 4mm pads for the VRMs. I wonder if this may be partly to blame for the AMD cards dying prematurely.

 

It may effectively allow the core to use the extra fin space I suppose, I would normally say VRM cooling is secondary but I am not sure how far is too far on that.

 

This is what happens when you give a guy a Dremel and he has too much time:

 

Lol, does it actually help any to cut out the metal?

 

Sure does mate! Compare the temps after playing Watch Dogs for 30 minutes. Ambient temp was 25C in both cases.


CPU benefited the most with a 4C reduction, while the master 780M shaved off 2C and the slave 3C.