M6700 Heatsink swap/repaste

Here is a quick guide and checklist as well as pics of my own heatsink swap. Lanbot pm'ed me about the heatsink being available and after he did the swap, I decided to do the same.

So first, why this writeup when Dell provides disassembly steps, well I did notice that their disassembly guide does have a few mistakes probably because they pulled some of their pictures from older disassembly guides.

Before we proceed, just a warning that you are dealing with electronics that are sensitive to static electricity and delicate laptop parts so proceed at your own risks and take as much time as you need (don't rush it).

Ordering a new heatsink​

If you want to order the 55W heatsink, the part # is 0CRYV5. Also be aware that Dell kinda overpackaged mine so it may be the same for you, here is the box they used to ship it, talk about overkill:


The heatsink should come with a total of 4 thermal pads + pre-applied paste on the area where the CPU will make contact with it. If not all pads are there, don't worry, you can use the pads from your previous heatsink. I'll get to how to handle them later on.

Preparing the heatsink swap or repaste​

To repaste or not to? If you order a new heatsink, Dell will ship it with pre-applied thermal paste. However, it is rather thick paste, not unlike putty and there is an awful lot of it. It will get the job done though, so if you feel uncomfortable with repasting, just use what Dell provides. To give you an idea of how much paste Dell uses, here is a comparative pic below, on the left, there is a stock Intel heatsink with pre-applied paste and a Pentium 4 desktop CPU under it. The Pentium 4 has a heatspreader of the same size of other more recent Intel CPUs. On the right, there is the Dell 55W heatsink and an i7-720qm. The die of the 720qm is bigger than that of Ivy Bridge CPUs and by quite a margin, there is a photo of my i7-3720qm later on in this thread.


Required tools:

• PH1 and PH0 scewdrivers, JK 3.0 and JK 2.5 screwdrivers will also work.
• Isopropyl alcohol (90% + ) or another mild solvent, do not go with something stronger than acetone. Note you can go with 70% isopropyl alcohol, but it will take longer to evaporate. Personally, I used 99% isopropyl alcohol.
• Q-tips or other lint free wipes to clean the old thermal paste.
• A pair of tweezers, there are some delicate cables and
• Dell's disassembly guide which can be found here: ftp://ftp.dell.com/Manuals/all-prod...bile/precision-m6700_Owner's Manual_en-us.pdf.
• I strongly recommend and anti-static wristband, an ESD mat might be a good idea too, but the wristband will be enough. If you decide to go with neither, make sure to ground yourself before proceeding.
• Thermal paste is or isn't optional depending on what you do, if it's just a repaste, you'll need some for certain, if it's a heatsink swap, it should already have some paste on it.

Disassembling and removing the heatsink​

Now, it is time to pull out that M6700 manual that you printed (you printed it right?, if not, I hope you have another computer close by because you're going to need the manual). Only a partial disassembly is required, the list of what you need to remove is presented at the beginning of the removing the heatsink section in Dell's manual, but here is the rundown.

What I removed and in what order, you'll notice that my order differs from the one presented in the manual and there is a reason for that. I will also provide the amount of screws for each part that you need to remove so you can easily keep track of them and there is an awful lot of screws. Don't loose the screws, they are hard to come by, I got spares myself, but only because I took them off from laptops I was sending to be recycled before sending them. Dell may be able to help you with that in the event that it occurs. A good way to prevent that is to use a small box with compartments so that you can not only prevent the screws from falling off of your workspace, but also sort them by component. Some screws are smaller than others so also be careful with that.

Before going through the list of components I provide, there are some steps presented in the manual which I don't detail here like removing the cables for the fingerprint reader, smartcard reader, etc. Be sure to disconnect when indicated in the manual. Be careful, there is a mistake in the guide about the bluetooth module, it is not in the battery compartment like it is shown in the removing the bluetooth module section. You'll see where it is in the steps for removing the palmrest.
Components to remove:

• Battery (no screws)
• Keyboard trim (0 screws) I removed it early because it is a delicate part and I prefer doing it when the laptop is stable on it's rubber feet. There is one feet on the battery, but I prefer having the battery removed for safety.
• Keyboard (5 screws)
• Bottom panel (2 screws)
• Primary drive (1 small screw and 4 to 0 regular screws) Depending on whether you have your main drive set to be easy to eject or not, the amount of screws will vary. The 4 M5x2.5 screws are labeled H for hard drive
• Secondary drive (3 screws)
• Optical drive (1 screw)
• CPU fan (2 screws) also be careful when disconnecting the cable for the fan, only pull on the connector, tweezers can be handy for that. If you pull on the wires and tear them from the connector, you'll have to order a new fan and your laptop will be unusable in the mean time.
• Palmrest bottom screws (13 screws) They are all labeled P except one and shown quite well in the manual. The one that isn't labeled P is on the left of the laptop (when it is upside down) near the fan exhaust and it is located left of a screw labeled D. Be sure to remove the screw to the left of the one labeled D.
• Palmrest top screws (10 screws, 3 small, 7 regulars) Dell's manual shows 12 screws, but unless I can't count anymore, there were only 10 for me. I do not have the fingerprint reader nor the smartcard reader so the layour might be slightly different for those who do, but I doubt it.
• Cables, there are some cables to disconnect here that I will list and there may be more depending on your configuration. You will at least have to disconnect the cables for the volume buttons, power button and speakers. Be extremely careful with the speaker cable, it is that small connector with the wires instead of the ribbon cable and it is extremely delicate, use tweezer and only pull on the connector.
• CPU heatsink, that one is pretty straightforward, the screws are attached to the heatsink, so don't try to remove them, simply unscrew until they disengage from the backplate on the other side of the motherboard. You should be able to confirm that they are disengaged visually.

That pesky unlabeled palmrest screw:

Installing the heatsink​

Now that the heatsink is off, you can inspect how much dust is in it as well as the GPU heatsink and use canned air if needed. If you are re-using the heatsink you just removed and it is dirty, now is the time to take an old toothbrush to it and clean the heck out of it now that is isn't in the laptop anymore. It may generate some static, so make sure to discharge any static before getting back into the guts of your M6700.

The next thing you need to do is get rid of the old thermal paste on the CPU, so take out the isopropyl alcohol and Q-tips. It will be rather dirty and you may want to let the alcohol seep into the old paste a little before removing. You can use the Q-tips to apply some alcohol on the paste. Some thermal pads may have stayed on the components rather than the heatsink. You'll want to remove them, use tweezers, not your hands. If you were missing thermal pads, now is the time to put them on the new heatsink. You'll recognize the pads by their color and texture. They aren't unlike chewing gum and are usually white/beige, grey or blue. They may come in other colors though. There is a total of 4 thermal pads, three for the power regulation circuit and one for the PCH (Northbridge if you prefer).

Dirty CPU:


Once clean, the CPU die surface should be mirror like, just like the i7-720qm shown at the beginning of this guide.

If you are repasting, clean the CPU heatsink surface as well until there is no trace of the thermal pate that was on it. Make sure everything is dry, do not touch the CPU die with your hands. Yes, I know that is obvious to most of you, but I'm being careful here.

For those who are repasting, do not put too much thermal paste, a little extra won't hurt, but don't go nuts with the amount of paste you use. Here is how much I used and even that is overkill, but I once fried a part by being stingy with the paste so now I always put a little more. Also, I find that die shape to be the worse, it's much easier to control the amount of paste with a square die, just use a drop the size of a rice grain or pea depending on the die size. That die slim and long so it is hard to get just the right length and width out of the paste syringe, if you can manage it better than I did, you'll likely shave off a few more degrees. The stock Dell paste was also slightly damaged during shipping and I wanted to avoid the risk of air bubbles.


Now it is time to screw the heatsink back in place, there is a plastic film over the fin area of the heatsink and make sure it lays flat against the top of the GPU heatsink, it may take a bit of fiddling to get in place. Now it is time to screw the heatsink in place. The screws are numbered, you want to tighten them in that order and tighten them like you would car tire. Tighten each a little in the given order, you should finish tightening screw #1 first. This will ensure even contact between the heatsink and CPU. Make sure the screws are tight, you want a good amount of pressure on that heatsink, but don't overdo it. Once you feel like the screws don't budge, try giving them half a turn and that is about it. Use a small screwdriver if possible, that way the amount of force you can apply is still limited.

Here you go, a brand new heatsink:



All that is left is reassembling which is in my opinion the most stressful part. Got at it in the reverse order of the disassemble. Make sure that all screws are back where they belong, you don't want to end up with a "spare screw". If you were methodical in taking sorting the screws, it should be relatively easy.

Finally, here is a 10 minute stress test on AC power, max temp ~87^oC, that is much better than what I was getting, but I will have to run wait until I run simulations to really get a grasp of the exact difference in temps, I know what temps I was getting when crunching numbers. I didn't run many stress tests and my simulations are more dynamic in terms of CPU usage.

 

Nice! +rep

 

Thanks, I did notice different fan behavior now that I've had more time with my M6700, it takes longer for the fans to kick in at full speed even when I am abusing the CPU. There are some things I wish I had monitored a bit more like how often the CPU enters burst turbo mode since it can have a rather spectacular effect on temps. For those that do not know what burst turbo is, the last two generation of mobile core i CPUs are allowed to go over their TDP for short amount of time. You can see the various maximum heat dissipation limits for both prolonged turbo boost and short in my stress test screenshot. They are respectively 45W and 56.25W, I did notice that sometimes the burst turbo kicks in and TDP usually climbs to around 50W and it is then followed by a temperature spike. Burst turbo may also be responsible for the fans kicking in sometimes on AC even when doing light work, I know I said the fans never came on, but I was actually mistaken, they no longer do so on battery, but they still do so once in a while on AC when I'm using Zune, but they still do so less often.

I guess I'll have to monitor TDP closely sometime to see if it coincides with a short burst of the turbo.

Monitoring the CPU used to be so simple with Clarksfield, but now that turbo has two settings as well as more current draw allowance, it makes things a bit more complicated.

 

Thank you for the post! How much did you pay for that heatsink?
You might be interested in revealing hidden Windows power options to get something like this http://i.imgur.com/r6vPU.jpg

 

The heatsink itself was about 15$ plus shipping, rather inexpensive really.

 

I just ordered mine today and was looking over your directions. The part number is actually 0CRYV5. It's also noted as just CRYV5 on my invoice, which I Googled to find that some other online store is already selling it separately (though at a considerable markup).

We'll see how it goes...

 

You are right, that was a typo that got through, fixed the part #, thanks.

 

Hey Tijo - Thanks for this.

I'm kind of new at this high-performance machine and its maintenance.

So I ran a 5 minute XTU stress test on my IPS machine and core 4 (#3) touched 212F a few times in the second half and noticed that throttling kicked in the equivalent of 10%.

From all my time in the threads never quite understood exactly if that throttling is engaged when temps exceed their max. If that is the case then am I running a bit hot and could consider a repaste sometime in the near future?

 

Intel has built in safeties in terms of CPU temperatures to avoid thermal damage. As soon as the CPU gets to the max prescribed temp (T[SUB]j[/SUB]), it will throttle. For Sandy Bridge, that max is 100 Celsius I think so that would make 212F. If that maximum is hit, the CPU will throttle until it cools down to a certain point. It could just be dust in your system if it hasn't been cleaned in a while, a repaste would definitely help lower temperatures, also a stress test is just that, it tends to push the hardware beyond what most programs do so it may be worth checking whether your usual workload gets the temps that high. If you're hitting T[SUB]j[/SUB], then there is no need to repaste, but it's still something to consider. You could also ask to have it repasted I think. Your CPU temps are also quite dependent on your ambient temps, if it's 30 C where you are it's going to run hotter than what I get, it's usually 24 C in my office and I consider that too hot.

Your throttling is very minor though, I have seen some people on NBR hit ~800 MHz because of throttling.

 

Thanks for the common sense.

Re-ran the stress test with power settings on Ultra-Performance (prior was Balanced) - stayed about 10 Deg. cooler and never hit 100C (212F).

Good insights - don't think I use 100% of my CPU very often and monitoring now with XTU can be more informed. Also the coincidence of the fans ramping up during short turbo boost explains that elusive behavior during lite-work.

With the tools you gave me I'll be able to watch for any futher degradation. For the time being everything seems to be within acceptable ranges so I'll postpone.

Before my EOL I'd like to have at least one CPU repaste added to - things I've done.

:thumbsup: