Heatsink mod! Must read it if you use Fan control!

the site seems like a good source for a wealth of laptop fans and assemblies - could be good for looking for mods and perhaps a more efficient fan.
http://www.laptopfans.co.uk/. Have a selection of noiseless fans too - probably magnetic levitation bearing types.

Update: hmm seems my work's virus scan is picking up a trojan when clicking on the acer link there. BEWARE.

 

anyone know if these heatsinks have enough clearance?

http://shop.aquacomputer.de/product_inf ... ts_id=2043

the profile looks good...

 

dont know but i think they are to high

 

my A150 already uses a maglev fan

phil

 

hmm yeh i think there all maglev's in the One's. Wonder if theres anythinng better....

 

I just removed the thermal pads in favor on as5, but it ended up taking the better part of two hours. The problem was that the stock heatsink wouldn't make solid contact with cpu, vga chip, and northbridge at the same time. The cpu area always makes solid contact b/c there's a depression formed into the sink. However, the VGA and nb were especially painful to make full contact with. I ended up bending the hell out of mine to create a shallow dip in the center line to hit the vga chip and forcibly lowering the nb sink by at least a mm to compensate for the ridiculously thick tape there. It seems 2-3x thicker than the vga and cpu tape. I really don't suggest trying to replace the tape on the nb with paste, just recycle the tape from the vga area by being very careful about pulling it off. as for temps, well as5 has a burn in period, so we'll see.

My biggest disapointment, though, was that the heatsink wasn't held in by spring screws. It would vastly improve heat transfer with any interface to have greater pressure, and would have made reapplying the paste an extremely simple process.

 

My simple method for getting a perfect contact pattern between the cooler and all three chips after removing the thermal pads.

1) remove thermal pads.
2) cut small sections of wax paper the size of the thermal pads.
3) apply a thick layer of two part epoxy thermal adhesive where the three thermal pads mounted on the cooler, place the wax paper on top of the adhesive.
4) mount the cooler before epoxy thermal adhesive sets up, and then wait.
5) remove the cooler, discard the wax paper, clean wax residue from both parts with alcohol, install cooler with CPU thermal compound.

The epoxy thermal adhesive will make a perfectly formed shim betwwen the cooler and chips.

 

Hi Woofer, I just received my AS5 and want to apply it. I'm a bit confused by your post as you suggest there are three thermal pads, while on this picture I can only see two. Also you recommend leaving one thermal pad in place on the NB. Doesn't this thermal pad make it even more difficult for the heatsink to make contact with the GPU and CPU?

Thanks for your suggestions!

 

That picture show two blue thermal pads and one gray thermal pad = 3

 

Ah, so the grey thermal pad is on top of the GPU? (hadn't recognized as a pad..)
SO best is to replace the grey pad with the blue one, because that one is thinner. That will lower the heat sink making contact possible with the CPU and NB. Is that correct?

 

Yes, the blue pads are half the thickness of the gray. So it you swapped the GPU pad from gray to blue the three chips should be able to come in contact with the cooler at the same moment.

 

Thanks, I'll try tonight and post the results!

 

I was just guessing as to what the nb and graphics chipset were. The smallest die is certainly the Atom. Now that I've been looking it up, the larger die is probably the controller. As for the component off to the side corresponding to the grey pad, it looks like it might be some variety of inductor, I'm not particularly sure though. Checking through the AAO service manual doesn't really help much.

I definitely manhandled my heatsink assembly while trying to get all three surfaces to make contact, I wouldn't recommend doing so if you haven't got the right tools to make precise bends. Replacing the grey pad with a blue pad might be pretty close to the correct height, but it's hard to say whether it'll be thick enough. It would probably be safer to use a new interface of similar thickness on the side sink, although I'm not sure it's entirely necessary to go nuts getting it perfect considering that it's at best an extremely indirect contact to the heatsink. The heatsink itself isn't exactly stellar anyway - pretty much just a duct that touches the chips with a fan that blows over them rather than the heatpipe heatsinks that have pretty much become the standard in confined spaces like laptops. If you damage it, I can't imagine it would be very difficult to remanufacture one out of a small square of aluminum and a spare fan.

 

Below is a picture I took of the heatsink after I verified that the contact was correct. Obviously too much paste, I wiped it off, reapplied, and reseated once I had confirmed everything was at the proper height. The guidelines etched into the sink reflect the arrangement of the chips on the board itself. The screw tabs look bent out of place because they are - The heatsink doesn't use spring screws, as I mentioned before, so screwing the heatsink down as it was before leaves a sizable gap that it was thickness of the thermal pads. The CPU and controller chip are in line with the triangle created by the three screws, but I really wish there had been more mounting points so that the sink for the inductor (best guess) is actually had down by direct pressure.

I also found that crimping down the fan shroud does indeed help isolate the movement of the fan a bit more so that noise goes down a bit, as has been mentioned before on this forum.

[attachment=0:3kcshpui]heatsink closeup.jpg[/attachment:3kcshpui]

Regardless of difficulty of getting all the surfaces to mate properly, it was worth the effort. My temps went down considerably, by about 5-10 degrees depending on my usage and should improve as the AS5 settles down. When the fan does kick in, the temps drop much more quickly than before, and remain there for much longer.

 

I've spent pretty much all evening changing the cooling system on my AAO. And I'm quite disapointed by the results:

Code:

Before mod:
Idle (10 mins) 32'C
Movie (10 mins) 42'C
After mod:
Idle (10 mins) 30'C
Movie (10 mins) 40'C

Only two degrees! And I changed the thermal pads, added a homemade heatsink and covered the airduct..
You can see the pics here: http://www.flickr.com/photos/36400994@N ... 210217056/
Please let me know if I did anything wrong..

PS I know I should have tested the temp after every step (being: the thermal paste, the heatsink and the cover), but I just didn't have enough time..

 

Just some more info:

The reason I wanted to perform this mod was mostly to keep the fan from spinning as much as possible (I'm running OS X without software fan-control). Also I expected the new "heatsink" to block some of the noise. Unfortunately the fan really isn't any less noticeable.. I do think the cover is making the air flow more efficient: the flow to the outside feels stronger.

About the third thermal pad (previously referred to as the grey one.. ), I have replaced it with the blue one. When I attached the the whole heatsink (duct, fan and all) it wasn't properly touching the "inductor", however I expect (or I should say hope) it did after I reassembled the whole thing as the duct is pushed upward and touching the "inductor".

People that performed one of these three mods (the "heatsink", the duct cover and the thermal paste) said they saw an improvement of 5-10'C. I have combined the three and I only have an improvement of 2'C. Either I did something wrong or these mods are only helping if you're cooling passively (using fan-control to disable the fan).

 

You realize that the temps you're reporting are already far below what the rest of the community typically gets? My 5-10 degree drop is from 55-60 idle and 65-70 under load to 48-50 idle up to 60-65 under load (i didn't play much with the fan settings yet. Running at 30C is already incredibly low, that's between room temperature and human body temperature. I would be extremely surprised if you reported the same temperature drops as those running under heavy load.

The AAO runs much cooler and more quietly under Linux variants with optimized kernels or under OSX, since it's essentially linux based. SSD models also tend to run at lower temps, if you've got an SSD model.

As for the noise, I would definitely suggest running fan control software if it's available for your OS. a1ctl and aa1fancontrol have essentially the same results in vista, and i think there were some solid fan control programs in the ubuntu forums. I suspect that the ducting also creates a sort of echo chamber effect so that although the mods may have improved your cooling processes, the decibel level is being artificially enhanced.

Does the fan at least run for shorter periods of time after all these mods?

 

Hi,
I admit 30'c sounds low, but with almost full fan I don't think it's impressive. Unfortunately there is no fan-control for OS X. My main goal was to have the fan kick in later. However I have no reads on decibel or RPM, that's why I used temp as a proxy.

There is no improvement in the fan activity. It even feel like a increase in activity, but that could be psychological....

I'll restore my Windows install and see how the temps are under activity.

 

OS X has nothing to do with Linux. And unfortunately there is no optimized kernel for OS X. I do use a kernel that supports hyperthreading and speedstep management.

 

OSX is a Unix-based OS, so is Linux's many distros. But OSX has nothing to do with Linux. I think that is the part where you are getting confused.