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Question

Thermal Paste

Apr 1, 2012 10:04AM PDT

What are t he problems, issues, if one uses too much thermal paste on the heat sink and cpu cover? I found it very difficult to try and spread the paste evenly across the cover and heat sink. I used one tube initially and waited two weeks too look at it and it was still tacky and I could see it was not completely covering. I wiped off and added three tubes this time and used a little tad of cardboard to spread over the cover and heatsink. Maybe I am paranoid but it seems that my fan is running more and louder than it did before. Thanks for your help.

Discussion is locked

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Answer
First, it should never dry.
Apr 1, 2012 10:14AM PDT

Second, there is a well known discussion about folk that put on fresh compound and then complain the CPU is hotter. Well, the CPU HEAT SINK IS HOTTER because the heat is moving more efficiently to the HEAT SINK!

Now that we have the heat making its way to the heat sink, the fans may indeed rev a bit more!

Sounds like you fixed it!
Bob

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Answer
Application procedure
Apr 4, 2012 5:07AM PDT

Actually you need hardly any at all, it's very minor in what gets used. Your statement of using 3 tubes suggests alot being used, way over the top. While you can use a spreader, I find using my finger quite capable and normally has sufficed for the many yrs. of doing this. Here is alink that provides what the manufacturer of thermal compound offers to apply the paste:

http://www.arcticsilver.com/instructions.htm

The above applies to any paste that is similar. Note the various cpus even targeted. good luck

tada -----Willy Happy

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Thermal paste.
Apr 4, 2012 11:52AM PDT

I started out with a pea size of paster but I could not get it to spread and cover the cpu cover which is why I used what I did to cover the heak sink and cpu. Is it possible I may damage my cpu unless I remove and reapply the paste? Thanks.

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How is this different from original HSF?
Apr 5, 2012 2:05AM PDT

The way this all works is the transfer of heat from one area to another. That means a flat metal surface from one to another in typical setups. The paste is used to fill the micro-gaps/grooves on such metal surfaces and provide a more uniform contact and transfer of heat. If spread paste where no metal to metal contact would ever happen it becomes an insulator and basically causes non-transfer of heat. If too thick, it can't do its job fast enough, if too thin it is less effective/efficient. Thus, you see why the paste has to be just right or close to it. Those instructions from that link I provided should be enough to guide you. You need place only a "glop" on that metal cpu area itself, NOT the heatsink. When contact with heatsink to cpu metal cover will be final spread by contact after being locked/screwed down. Of course, before doing anything the areas of contact have to be 100% cleaned of old paste/compound.

What may happen if this never seems to be enough to get the heat away from the cpu is either you have an inefficient HSF(too small or rated for cpu) or the application was improper. To add to that, maybe the actual HSF just isn't right, it's too cumbersome, thus review what that HSF was bested used on. Further while this is directly for cpu use, the overall cooling of the PC case comes into play as it has to deal with that heat extruded from cpu exhaust it out, so you see the whole process has to beneficial. If what you have just doesn't cut it, get another HSF(heatsink&fan) setup and redo again. Alas, you never provided details of all this is being done on, review what you have and check and verify all is well.

tada -----Willy Happy

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Thermal paste
Apr 5, 2012 7:33AM PDT

I cleaned off all of the paste I put on before. Had one more tube. Followed the video, pea size in middle of cpu cover and used business card to spread. Was happy with the way it worked. Got an even spread on the cpucover and made sure I had a good cover in the middle. So many thanks. Before I leave this thread, can you tell me if should begin feeling hotter air out of the fan vent.

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Replacing thermal paste is only to restore or increase
Apr 5, 2012 7:40AM PDT

the efficiency of heat transfer from the CPU die to the heat sink. The total amount of heat generated is not affected. Thus, you should not notice any temperature change in what exits the box. If you could measure it, the heat sink temperature should rise faster from when cold but that's about it.

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Thermal paste
Apr 5, 2012 10:36AM PDT

Great that is what I am getting. I really, really apppreciate your help and avice. You have solved my problem

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Maybe, IMO
Apr 5, 2012 3:45PM PDT

If in fact the HSF is doing a better job it maybe adding slightly more to the heat exhaust. As long as it "exits out" will be a better result than anything else. However, while I've seen smoke tests to show what results can be had, I thought anyone does that for their home PC. The point being, if the overall results are good and remain so, then accept it. Beware, in the process of adding the paste, etc., you may have not pay attention to wire harness, etc.. We're talking "airflow" here so the less intrusions to that airflow allows it to be exhausted better or more efficiently which may add to higher heat exhaust. Having a temp reading. should provide the avg. of what you're experiencing using a thermometer if you like.

tada -----Willy Happy

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Thermal paste
Apr 6, 2012 2:54AM PDT

I will have to back and see it again. I remember seeing him doing something with the harness but will re review.

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Thermal grease
Apr 6, 2012 3:47AM PDT

I went back and watched five different videos and none mention the wire harness. Is this the harness which locks the cpu cover down?

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Get them out of the way
Apr 6, 2012 7:03AM PDT

Airflow is best done when everything of one item or another is out of the way, so any cooling, especially air cooled can do its job. Which is way some PC cases provide venting/tubing to directly exhaust heat build-up.

ie: if you place a plastic bag over vent, will it allow exhaust to be very good? No, it's blocking the exhaust. Same for your fingers or anything that gets in the way.

The thing I'm trying to convey is that airflow works best with as little as possible obstructions. Wire harness should be tied down or re-routed so they're not in the way as best as possible. It's part of the overall reduction of objects/items in the way. Checkout some gamer PC and notice the better ones have routed cabling, wire harness, tags, connections, etc. to the PC casing or plate.

tada -----Willy Happy

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Thermal paste
Apr 6, 2012 7:55AM PDT

I think I got you now. The wire harness for the fan. When I first took the fan off the wires were wrapped around the coil on the heat sink a couple of times. I did not rewrap the wires when I put it back . So I should route this as far dpwn as I can in to the case?

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There are some discussions on routing the wires.
Apr 6, 2012 8:02AM PDT
https://www.google.com/search?hl=en&as_q=how+to+route+cpu+fan+wiring

The key take aways are:

1. Keep them away from fans that could cut them or catch on them.
2. Keep them away from slots.

Item 2 was not funny as I had to break the bad news to someone they had a fan power cable across a slot and this was wedged in as someone tried to put in a card. They succeeded but ended up with a dead motherboard.
Bob
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routeing wires
Apr 6, 2012 10:48AM PDT

Yup - I have seen that happen a couple times - nothing you can do but get a new mobo - due
to one or more ram card tabs get bent out of the way and theres no fishing it out or
re-bending it - toast ... touchy stuff.
never try to clean dust out with a brush - use a light blower or vacuum.

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Application procedure
Apr 8, 2012 10:51PM PDT

Ok I got he paste. Where do I find your finger Wink

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Answer
How To Do It.
Apr 7, 2012 12:08AM PDT

Applying thermal paste to new CPUs is a daunting task if you've never done it before. It's a piece of cake if you have.

The first thing to do (after you've gotten yourself your new CPU, motherboard, and thermal paste) is to go out and get yourself some microfiber wipes.

If the processor is already installed, remove the fan and processor and, using the microfiber wipes and 91% isopropyl alcohol, clean off ALL the old paste from both the fan's heat sink and the processor chip. Depending on how long the processor has been in use, this could take quite a while but it WILL eventually come off.

If it is a new processor, you may still have to clean manufacturer-applied paste from the cooling fan the same as you would from an old processor installation, but this will be much easier. Just use the microfiber wipes and some 91% isopropyl alcohol and VERY carefully clean the top surface of the CPU. Be especially careful not to touch the top of the CPU contacts on the bottom of the processor.

Now you "stain" the CPU. Again taking special care not to touch the contacts, apply a small amount of the thermal paste (I recommend Arctic Silver -- it's easy and its applicator tip is JUST right) to the top of the CPU, use a credit card or something similar to spread it thinly over the entire top surface, and then wipe it off carefully ("carefully" is the governing philosophy throughout this entire procedure) with a microfiber wipe WITHOUT any alcohol. This fills any irregularities in the CPU surface with thermal paste and it will run cooler for life.

Now, install the stained CPU in the socket and clamp it down.

Next, apply the thermal paste to the CPU. For most Intel chips, this is done by applying the paste in a thin vertical line centered on the CPU cap and running about 3/4ths or so of the total CPU height. For most AMD chips it is applied as a dot in the center of the chip about the size of a very small pea or a large match tip.

Now, carefully install the cooling fan. The installation of the fan's heat sink should spread around the cooling paste correctly. You don't need to spread the paste at all -- installation of the heat sink does all the work..

A little excess won't hurt. A LOT of excess could. Thermal paste doesn't dry hard for a very long time, if ever. Indeed, if it does dry hard, it's time to think about cleaning and reinstalling the thermal paste.

Also, keeping your computer clean inside will make it run cooler. They get gummed up with all this dust remarkably quickly, and can be cleaned out pretty well with those little cans of air. Do it outside, though -- they collect GOBS of dust even when you keep your home or office immaculate.

Two excellent freeware applications allow you to check and/or continuously monitor your CPU temperatures and other aspects of your system's ongoing operations. One, which is just a nice clean monitoring application, is the open source Open Hardware Monitor, available at http://openhardwaremonitor.org/ . Another, which enables you to do stress testing and diagnostics in a wide variety of ways, is OCCT ("OverClock Checking Tool"), a French application that lets you load your CPU, RAM and GPU to 100% capacity with various data sets and graphically monitor their temperatures under load. It is available at http://www.ocbase.com/ .

I hope this helps. I followed these procedures building my Core i7 machine and the CPU runs normally at an exceptionally cool 34 degrees C in normal usage. Even blasting it continuously for hours at 100% on all four CPUs, and all of its 16GB of RAM I can only get the maximum temperature of any of the four cores up to 54 degrees at peak at the 3.8 GHz burst speed. I could probably overclock it over 5 GHz without having it even start to breathe hard but the speed is adequate for now and I am looking for reliability rather than dominance.

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Thermal Paste
Apr 7, 2012 2:49AM PDT

Great info; I have read numerous articles, viewed videos, and never saw the part about staining the CPU. I will know next time. As I have just cleaned and reapplied this week, how critical is it?