Over the last 10 years I've found laptops throttle the processor speed in order to keep fan noise down. I prefer the fan to run noisily, and the processor to run at full speed. I've developed tried and true mods for lappies and have demonstrated their effectiveness.
I have two Lenovo W541 laptop workstations with I7-4940MX processors and discrete nVidia graphics. On one I overhauled the cooling. Copper shim between CPU and hsf, AS5 on both sides. Shims between hsf and inductors near CPU and gpu, and shim on the gpu.
Used 'thinkpad_acpi' Linux kernel module to set fan to max speed. Ran mprime (prime95 for Linux) AND Unigine Heaven, alternating, to cure the AS5. Then ran mprime. Temps were slightly high. But laptop processors tend to run hot.
The I7-4940MX is a 3.1 GHz, 4.0GHz. Turbo processor. The modded machine ran at 3GHz. continuously running mprime, for weeks. The unmodded machine with the same max-fan-speed software tweak and stock thermal-interface material, throttled to 1.7GHz. at the same running temps.
Clearly, laptop manufacturers are robbing performance off the top, by inferior cooling hardware and materials. Granted, getting the cooling mod to all fit together correctly with smooth, flat surfaces requires hours of work and materials not normally found sitting around the house.
I normally do not mod the CPU die. I abrade copper surfaces down to 1500 grit paper, and then polish with scapings from a bar of buffing compound. Everything is done on 1/2" plate glass to maintain flatness. The final mirror polish is done with the compound granules on a clean, damp cloth.
Desktop processors mostly have slightly raised corners, so smoothness is not as much of concern. You're going to get thermal-interface compond completely covering the center of the processor. The ideal is to fill the microscopic gaps between the cpu die and the hsf, but where there is metal on metal, have it be.
Metal to metal provides 100s to 1,000s times the heat transfer of thermal paste. But, on a desktop, there are more effective cooling solutions than moving air. Most user are satisfied with their laptops, because the processor doesn't run full speed long enough to make a difference.
But I enjoy tweaking, and I do processor-intensive work, like batch editing 100s of large images, video rendering, security testing, password recovery, network testing; that are all severely compromised by poor, stock laptop cooling solutions.
First I want to thank the community, who have inspired me to do this project.
I will give you guys the chance to follow me on this journey.
I hope you will all help me come up with ideas, techniques and parts that could become handy.
This modding may be possible to convert to allot of laptops.
Here is the measurement of the went hole.
77mm X 16mm
I have 2 ideas for what can be done.
I own a Clevo P151SM1 that I bought in a hurry last year after my Alienware died on me. It's done a good job of playing everything I've thrown at it but lately, it's been shutting itself off when I play certain games or graphics-heavy programs. When idle it sits around 38C which is great. But when I get into a game it skyrockets up to 97C as the last recorded temp before it shuts itself off. I've cleaned the fans and keep it on an elevated cooling pad (no fans on the pad cause I broke them) but it gets plenty of air. I know that 97C is probably damaging the card and I don't want that. Does it look like I'm going to have to repaste it? I've attached my latest readings if that would help.
Since I switched over to a single card I have all this extra space and a heat sink and fan no longer in use.
I was wondering if there would be a cheap alternative to buying the duel/6 pipe heat-sink - It is pretty expensive.
Is there a way to mod/bridge the one two I have now . I attached a photo of what it looked like before I switched to a single card. Basically the right (slave) is empty.
Of course I am not expecting a mod that would work as good as the 6-pipe heat sink built for my system. But it would be cool if I could use what I have and get my temps a little lower.
Over the last month or so, I've been planning on overhauling my (slightly dated) P157SM to give it better cooling, and possibly higher performance.
There were a number of sources I used for inspiration, and I'll attempt to document all of them later on, but first, pictures!
This is the first modification I made. I increased the opening of the CPU fan to allow more air to go into the fan. As I recall, it helped with idle temperatures but I don't remember by how much.
This picture shows how much I increased the opening by, I didn't do just that bit and stop
Next up, I increased the width of the intakes directly over the GPU and CPU to reduce ambient heat buildup in those areas.
I ultimately decided that increasing the width was not the best route to go (and it was quite ugly) so I decided to simply remove the vents
I used some diamond mesh to cover those areas, but I don't have any pictures of that at the moment.
Next I used some HVAC tape to direct the air flow from the CPU fan into the heatsink and not out the tiny gaps in the area.
Then I swapped out the heatsinks (originally I ordered this from XoticPC and went with their copper cooling upgrade (I was young(er)) for some bigger ones.
Everything is all nice and snug
And finally with the lid back on.
With the changes made between cutting the vents, and the last picture, I was able to drop load CPU temps ~5C which I thought was pretty nice.
My goal is to also get rid of the vent over the fan, but I haven't found time to do it. I'm also planning on lapping the GPU heatsink, which will, again, take time.
I'll post more updates as I make them (and post the benchmarks I've already done).
So I have a 780M at the moment (I'm planning on going to a 980M, though I may just wait for the Pascal GPU's to come out) and I decided to lap the heatsink, since I'm planning on overclocking it.
Fresh of the block
400 Grit (10 minutes)
600 Grit (10 minutes)
800 Grit (10 minutes)
1000 grit (7 Minutes)
1200 Grit (7 Minutes)
1500 grit (about 25 minutes for this stage)
And I thought it looked pretty smooth. One of my references mentioned cutting off the little tabs on the block, since they're mostly there for adding additional pressure (since the plate is usually warped) and I wanted to just lap the area directly over the GPU die (plus I don't really have a good place for grinding copper with my rotary tool).
For the paste I used http://www.coolermaster.com/cooling/thermal-compound/mastergel-maker/ which I went with based on the favorable review posted at http://www.play3r.net/reviews/cooling/cooler-master-master-gel-maker-nano-thermal-paste-performance/ and the pads are Fujipoly high end (didn't think I'd need to go ultra).
I also added some little sinks on to the heatpipes, though they might be suspect (more on that in the results below).
And I sealed up a gap in the fan to direct more airflow through the larger fins.
I also used from more HVAC tape to try to prevent ambient air from being drawn in to the fans, but this too might be suspect (it might be needed to draw it away, since where else is the heat from all those fins supposed to go?)
And the results are... interesting...
So the initial benchmark had a 5C drop in temperature, but the following results aren't as promising.
In fact, the stress test results appears to be higher (I'm speculating that it'd be over 86C by 400 seconds).
I'm thinking that either the added heatsinks on the heatpipes are dispersing the heat before it can get to the fins, my lapping job wasn't so great, or I added too much TIM. I may try the washer trick from the p150 cooling threat mentioned below, but I'm spent on energy for this weekend.
June 3rd update
I finally got back around to working on my clevo some more and after a third re-pasting my temps are down (taking into account that today is hotter than when I first tested)
I suspect that my older paste jobs were either too thick, or I bent the heatpipe and kinda threw the plate out of alignment.
Modding my clevo in general:
Sealing up the gaps in the fins:
Additional cooling ideas: