Overheating due to the "old" thermal paste...

This experience may be interesting to those who have problems with overheating no matter what they do.

I used to have a pretty OK comp with overclocked (feature in BIOS), undervolted (NHC) CPU and overclocked ATI x700. And that worked well at max 72 degrees C for CPU and 85 C for GPU after hours of playing games. And the summer came. Temps went a bit higher, but cooler pad managed to keep it under 75 C.

For I while I was suspecting that something was wrong with the cooling, because the temp would oscilate too much. I mean it would be like 51, and after few secs it would jump near 75 under a short 100% load!

And then today I was playing Operation Flashpoint FFUR mod 2.0, and comp suddenly restarted, and when I logged in, boot process in WIndows would need another minute or two. NHC would give me warnings about 80 degree limit. I tested my usual set of tests (Crimsonland in demo loop, with Everest GPU and ambient GPU temp, and NHC for CPU temp) and the temp hit 95!!! Afterwards I realized some system files were damaged in a sudden restart and decided to reinstall windows (after a year of testing every single new driver and software of my interest and MS beta software, I believe the time was for a fresh install) . Luckily my disks and accounts were set to another logical disk, so I could reformat easily and get back my settings in an hour or so.

I put my boot CD with windows sp2 and it would go up to "Starting windows" screen (still text mode) and after a few secs it restarted!

I checked BIOS, CD and suspected that the disk was dying, but then I remembered that during the install process, there was no advanced power management, and that CPU must had been at 100% load producing a lot of heat!

I opened the comp, removed heatsink, there was no dust or anything, and then I saw that something was wrong with the thermal paste. It was originally put onto the heatsink in the factory, but I personally have built the whole notebook from a barebone and was very carefully while applying the heatsink. It worked well for almost a year. When it was new it was sticky and "wet". Now it was dry and powderish. One whole part of the CPU core had a mark or a discolouration from heat! I touched the "paste" and it turned into dust! No heat transfer whatsoever! Half of it just disappeared!

I went down to the local comp store and bought 1,5 USD thermal paste with only 10% of silver, and the rest is zinc oxide, in a syringe. They were out of AS5. I have applied that paste onto the CPU, a very thin layer - and it is back to normal again - without cooler it never reaches 75 after 3 hours of gaming (overclocked, and undervolted). Heat transfer is great.

I tried it with the GPU, but the heatsink is designed for much thicker pads, so it didn't work and I didn't want waste time by removing all of the existing pads from memory, so I left it alone as it was. GPU reaches max 85 in games.

So how is it possible that the paste just disappear? I guess that originally it was some cheap silicon paste that gradually loses its features exposed to air and heat. It becomes dust and simply is being slowly removed in transport or with air flow.

Many people have problems with overheating, trying that and that, but in this case coolerpads, fan or undervolting will not help. If you can open your comp, check the heatsink, and remove it! Check the thermal paste or pad, maybe it is in a bad shape. Apply whatever thermal paste you have, Artic Silver 5 being probably the best. Search for ones with silver or aluminium in it. More silver the better. Clean the CPU die and heatsink. Creditcard is ok for that. Apply a very thin layer again using a creditcard type plastic, and reapply the heatsink. Check the difference under load.

I hope that can solve some of the problems with overheating

Cheers,

Ivan

 

Definitely agree that the stock thermal paste a lot of times is junk. The stock stuff on mine was some sort of black, generic stuff, took a while to remove properly (used isopropyl alcohol). After applying AS5, my CPU is more controlled temperature-wise, especially when running @ 100% for extended periods of time.

 

Wow... 75C! I guess I shouldn't be worrying about my 65-70C anymore, should I?

 

Of course not - most Intel proc will shut down at 100! Remember that GPU and CPU are under the same heatsink. GPU in my case after hours of gaming will reach 85 C (I tested and it works up to 120!) - so in my case my GPU heats CPU too!

Cheers,

Ivan

 

Hi Chaz,

Exactly - on idle you don't see the difference. But at 100% it surely boils an egg with ease. . AS5 has 99.9% silver. Artic Ceramique is also good (aluminium oxide based), but I so far cannot say anything against the cheap 10% silver compound (Fanner-Spire 700) with this thermal conductivity: 2,17 W/mK. AS5 has 18W/mK and ceramique has 14W/mK. Considering this - AS5 is clearly the winner. I wanted AS5 - it is only 5 USD a tube. But I needed something fast, and as I said it isn't bad so far.

Cheers,

Ivan

 

Some nice thermal paste reviews:
http://www.overclock3d.net/reviews....battle_of_the_goop_-_thermal_paste_comparison (Coollaboratory Liquid pro beats AS5 by 6 degrees C)
http://www.pugetsystems.com/pic_disp.php?id=6597&width=500 (generic thermaltake again is a good thing to have)
http://tech.vault9.net/forums/index.php?showtopic=21695 (generic thermaltake is an idle winner here)

Ivan

 

I've never heard of ShinEtsu G751. I'm guessing that's a Japanese product? (Name sure sounds like one). It's pretty cheap too. Just did a quick search on Google. $6 a syringe. Anyone got any experience with it?

75 C seems REALLY high...I thought notebooks ran at like 50 C. Or is that under no load and 75 is normal for a 100% load?

 

Hi who8mahrice,

I removed that pic, because it was in french and I couldn't understand the meaning of the numbers. But I have put some other links. Sorry for the change. But yes ShinEtsu seems to be a good paste.

50 on idle, 70 on load isn't bad I guess. Lower the better. I have an overclocked machine.

Cheers,

Ivan

 

Manufactures use thermal pads which are total crap. They have bad consistency and are a "one size fits all" attemp at mass production. Any experienced PC builder knows that each cpu model has a different ammount of grease/thermal paste that needs to be applied (e.g. p4 prescott requires rice sized amount, while a turion requires 1/3 a BB size amount). This makes the contact between the cpu and heatsink just right to dissapate heat better.

Well if you have ever seen a thermal pad they are relatively thick and there consistency is really bad. Because it is too thick and made of crap it wont dissipate heat well. I would say try to use some artic silver on the gpu and cpu, thier site has the proper amount to apply on it. The $5 tube will be more then enough paste for MANY, and I mean many, applications. Also it never hurts to dust while your in there. See if that helps.

 

The only reason for the change in amount was the size of the core. More paste does not mean it will keep it cooler. Plus most cores have an IHS now so they are about the same size. You basically want the thinest layer possible. All the paste is doing is filling in the microscopic gabs between the H/S and CPU so the heatsink is more efficient. If you put too much it will actually decrease performance.

 

That is why I used the credit card for removing the excessive paste. That way I have got really thin layer that proves very good. And I share the opinion about "pads". There is no way it transfers the heat like paste. I must try removing those pads from gpu and its 4 memory chips and measure the temps with paste.

Cheers,

Ivan

 

The highest mine goes at FULL CPU POWER is around 66~68C CPU....and even after HOURS of gamming the temp is still at 57C then goes down to 51 (idle at 65)

Ah......THE WONDERS OF THE www.ISTNC.com staff and ARTIC SILVER5