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How much thermal paste?

By esbo
Jul 7, 2010
  1. I put a good bit on when I changed to a x2
    processor, there was already some on anyway.

    I am wondering it i should have cleaned and put a thin film on.

    However there is not a lot of difference and remember I am using twice the processing power. so you expect more heat. + it is summer here.

    I have noticed sometimes when the fan comes on it is very loud as in very high speed occasionally.
    However it does go back off so it shows cooling is working.
    So maybe I am worrying too much.

    I will have a look at it when I change my memory when the post arrives from ebay.

    Anyone know the thermal properties of the compound compared to say steel?
    (heat tansfer in watts per second or whatever)
     
  2. EXCellR8

    EXCellR8 The Conservative Posts: 1,835

  3. dividebyzero

    dividebyzero trainee n00b Posts: 4,891   +1,258

    A reference for thermal conductivity...
    http://benchmarkreviews.com/index.p...ask=view&id=138&Itemid=1&limit=1&limitstart=1

    As for how much....about a rice grain sized blob. The more TIM you use, the worse the thermal conductivity will be. If using (now or in future) a direct touch heatpipe cooler I usually apply the same amount of TIM to it's mounting face to fill in between the heatpipes and the block they are embedded in, in addition the the "rice grain" sized application to the CPU.
     
  4. red1776

    red1776 Omnipotent Ruler of the Universe Posts: 5,219   +157

    I have experimented with many different application methods of Thermal compound in the hundreds of builds I have done and this is the most effective and the method I prefer. it is done with an exceeding thin layer and a razor blade. see attached (ahem drawing0 that Chef will give me a hard time about. :) If you like I can show you idle/load temp results with both exposed heat pipe, and through base heat pipe types of heatsinks. with the exposed 'direct touch' heat pipe type, I use a razor blade (brand new) and gently scrape the length of the pipes and then across the pipes to fill in the gap between them, and then as the drawing I attached. remember the layer is very thin, as in you read the model number through it. just one way of doing it, but has been very effective for me.
     

    Attached Files:

  5. esbo

    esbo TS Rookie Topic Starter Posts: 102

    OK I found this in wiki:-

    The metal oxide and nitride particles suspended in silicone thermal compounds have thermal conductivities of up to 220 W/(m·K).[1] (In comparison, the thermal conductivity of metals used particle additions, copper is 380 W/(m·K), silver 429 and aluminum 237.) The typical thermal conductivities of the silicone compounds are 0.7 to 3 W/(m·K). Silver thermal compounds may have a conductivity of 3 to 8 W/(m·K) or more.

    OK that's a little confusing.


    I am assuming from that that the compound I used, is around 100 (or more) times less
    conductive than copper.

    That does not sound very good but then it's supposed to be a thin layer, and it will be a lot better then air I suppose.

    I seem to remember mine had a good bit of compound on, more than a grain of rice I would say. I don't remember to well, I was more excited my getting the new processor up and running!!

    I would say the fan seemed to stay on longer than before after the CPU usage dropped but then obviously a X2 processor will generate more heat anyway + it's the hottest time of the year here so, that clouds comparison somewhat.

    Anyway there is no big problem really, the fan does go off in a reasonable time I think so no danger of damage or whatever.

    I should get my new memory in a day or two, so I will try and do a good job on it then, ie clean both the processor and the heat sink surfaces and then apply a small grain sized drop. I think it is natural to put more on rather than less just to make sure you have no air
    gaps.

    I guess any excess would be naturally spread out over time anyway.

    Also there is some sort of 'break in period' and I would say it seems better now than initially, in fact I am not too sure if I should bother now - lol.

    I may just 'leave well alone', but if I do re-do it I will be keen to see if it makes any difference, but I guess there will be a new break in time too!!
     
  6. esbo

    esbo TS Rookie Topic Starter Posts: 102

    Also I found this for artic silver (wiki)


    Arctic Silver 5 (AS-5)

    The current version of the company's eponymous thermal interface material, Arctic Silver 5, is a high-density compound of silver, aluminum oxide, zinc oxide, and boron nitride in a proprietary polysynthetic oil base. It is at least 88% thermally-conductive material by weight. AS-5 consists of three unique shapes and sizes of micrometer sized silver, in addition to sub-micrometer sized ceramic particles. It does not contain any silicone.

    Its thermal resistance is rated as less than 0.0045°C-in²/Watt.


    Unfortunately that is resistance not conductance, so not easy to compare directly with the conductance figures.
     
  7. esbo

    esbo TS Rookie Topic Starter Posts: 102

    Hmmm wel I got my memory but I had a lot of problems installing it.
    When I bother I got beeps, about 4, I switched off then.
    Seems I had not pushed them in hard enough or something, anyway I reseated them and it
    booted to the blue 'post' (?) screen but would go no further!!

    Anyway I decided to start removing the memory, I removed the top 256 meg which came originally with the machine, it had been in slot 1 but I had put it in slot 3, My old 1 gig stick in slot 1 now and the
    new 1 gig stick in slot 2..

    So I decided to remove that 256 meg in slot 3 and fortunately it booted up!!
    (Otherwise I would not be here!! Well maybe I would on my 10+ year old Cyric MII 300 but I do not much relish the thought of using that!!).

    I will leave that stick out for now, it's only 256meg and I have 2gig so that is fine for me, more importantly I have a working computer!!

    I also had a look at te CPU and fan, I noticed the fan was loose!! The clamp which secures it did not seem to be properly connected, I know I had trouble getting the clamp on before but I though I had managed it - apparently not.

    Anyway I just made sure I got the clamp on properly I did not bother with new paste or whatever as I had bigger concerns at the time, ie getting my PC to boot.

    One thing I did notice with the memory was that slots 3 and 4 a different colour they were blue, slots 1 and 2 (the only ones I had used before) were black.
    Is that significant? I had never used the black ones before so maybe that was the problem.

    I did see on this video that the slots may be colour coded as it shows different colours for DDR2 and DDRr3, obviously mine is just DDR.

    Mine should be all DDR according to the product guide.

    Maybe I damaged the memory? I am not sure, it did boot with the 256 stick in slot 3 but only to the post screen it never went into windows.

    Anyway I will perhaps make a separate post about the memory but at least I have a working computer, I will think about looking into the other issues later, I am just happy o have my computer and internet access at the moment!!
     
  8. esbo

    esbo TS Rookie Topic Starter Posts: 102

    I do have a new issue though, one core seems to running at about 90% the other is low about 5%
    however the system idle process is showing at about 97% but the CPU usage at the bottom of the task manager screen shows CPU usage as about 47%!!!
     
  9. EXCellR8

    EXCellR8 The Conservative Posts: 1,835

  10. esbo

    esbo TS Rookie Topic Starter Posts: 102


    OMG I am having nightmare with this, just to update on what has happened, I had it running on a single meg with no CPU usage problems, then I switched to the other one meg stick and the problem came back, then I though I might as well stick both sticks in and deal with the problem, however I had a problem booting (which I knew was due to a badly seated graphics card, so I took the extra 1 meg stick out and reseated the graphics card)
    Now it has booted up with no probs with cpu usage, but I am only on one meg, that is I think the same 1 meg which had problems earlier.

    SO I am pretty frigging confused!!

    OK thanks for the download, I will have a look at that, I had download something caller
    process monitor (similar but not same) but that was very confusing and I could not find anything that looked as if it might help.

    So problem is now that I do not have the problem, so I cannot 'debug' it, so I will have to try and get the problem back.

    I will try putting an extra gig of ram in to make 2 gigs, that should get the problem back, as I have never had 2 gig and no problems.

    Thing is I am thinking it is a hardware problem.

    I am going to have to reboot for the umpteenth time today and try the second stick of ram and see what happens.

    I am hoping it is hardware, something badly seated and that I have cured it, however I am not to optimistic. However I do like my PC now as it is with no probs even if it only has one gig of ram. it is better than 2 gigs an effective half a processor.

    OK I will reboot and swop now, with fingers crossed!!
     
  11. esbo

    esbo TS Rookie Topic Starter Posts: 102

    So I definitely have no problem now, just to make sure I did not imagine it, I have written it down here!!
    I have the new stick of ram in. I will add the 2nd stick now.
     
  12. esbo

    esbo TS Rookie Topic Starter Posts: 102

    :) :) :) :)

    Booted up with two cores and 2 gig of memory!!!!! :)

    I think it must have been badly seated memory or something like that.

    I am hoping so anyway!!

    I am probably going to want another reboot successfully just make sure the problem
    does not come back.

    Then I may have a go at putting the last 256meg stick in, but that's only an extra 10% now
    so I am in no big hurry to do that!!

    All systems running now!! :grinthumb
     
  13. esbo

    esbo TS Rookie Topic Starter Posts: 102

    OK I have rebooted again and all system go!!
    No problems, issue seems resolved!!
     
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