does thermal paste expire ?

[NTM2003]

Does thermal paste expire ?

 

[Bill_Bright]

No!

AS LONG AS the cured bond between the mating surfaces is not broken, thermal paste will easily last 10 - 15 years or even longer. But if the bond is broken, either due to rough handling during transport, or from the user twisting the heat sink to see if still tight then the mating surfaces must be thoroughly cleaned and a fresh new layer of TIM (thermal interface material) be properly applied.

 

[NTM2003]

It seemed to apply fine so hope it works

 

[Batou1986]

I assume we are talking about in the tube ?
If thats the case then yes it does expire.
I had a large tube of AS5 that started to separate after about 4 years, half of it was oily the other half was like dry paste.

 

[NTM2003]

OK mine was kinda dry but it came out hopefully it will hold for 2days

 

[peche]

Do you mean a tube, flask or pillow?
yes it does expire, you can see on back panel, also can get some storage advice, also exp date, lot and other important advice, instructions...

Already applied paste?
It expires and also dries, or burns or degrades, depending on computer usage, also about cooler, heatpipes coolers are well know for maintaining high temps, so this will make a bigger impact on TIM, compared to waterblocks that may reduce heat due cooling performance, but that's a little bit more complicated topic, also on some cases differences are minimal,
Some pastes as Coollaboratory liquid PRO / Ultra, Arctic silver 5 for example are wll know for long lasting lives,
Degrades its the better term for what really happens to TIM's due temps and cooling

Regards,

 

[NTM2003]

my cpu is running at 28-30c thermal status ok using real temp

 

[NTM2003]

this is just for 2 days order some more should be in 2 days

 

[peche]

my cpu is running at 28-30c thermal status ok using real temp

that's a excellent temp no worries, i wonder you are using the stock TIM pre-applied with your cooler,

Regards,

 

[NTM2003]

yes for now see my other thread on first build had problems with the h80i

 

[NTM2003]

http://www.techpowerup.com/forums/threads/first-build-log.211268/page-3#post-3268735

 

[Bill_Bright]

@NTM2003 - Perhaps I misunderstood your question. I thought you were talking about TIM already applied, not TIM left in an opened tube. So to clarify, once properly applied, TIM does NOT expire IF the cured bond has not been broken! Big "if", yes. But there's no reason it would break under normal use.

If you were talking about TIM in an opened tube, then that TIM has been exposed to the air. It also has not gone through any heat/cool cycles so what is left unused in the tube may become unusable - depending on the solvents used in that particular formula.

So the point is, you do not have to replace properly applied TIM just because x number of years have passed - again, if the bond remains unbroken.

There is a common misconception among enthusiasts who are not formally trained in electronics that because the "exposed" edges of TIM turns hard or becomes "crusty" that the product between the mating surfaces has somehow become ineffective. THAT IS NOT TRUE! Remember, the most efficient transfer of heat occurs with direct metal-to-metal contact of the mating surfaces.

The purpose of the TIM is ONLY to fill the microscopic pits and valleys in the mating surfaces to displace any insulating air that may have been trapped within. Years later, the TIM is still there and if the bond is unbroken, air cannot get in and occupy the same space. Therefore, the TIM does NOT need to be replaced just because years have passed - even if it dries out!

As an electronics technician since 1971 (see the link in my sig), I have personally worked on 15 year old radio communications systems where TIM used on solid state devices was still working perfectly even though the exposed TIM around the edges had turned brown, crusty and nasty looking.

See The Heatsink Guide: Info about thermal compound and note the following (my bold added),

Thermal compound normally does not get hard, it will stay sticky for years. But depending on the solvents used in the making of the compound, it may dry over the years. This is not a reason to worry; it will still do its job when dry, and there is no reason to replace dried thermal compound.

IF it was necessary to regularly replace TIM, don't you think the TIM makers would say so? After all, that would mean more money for them. But they don't say to regularly replace it because they know it is NOT necessary.

 

[Vario]

Arctic Silver 5 7 years after application was still working fine on 939 system, also was fused so hard it was difficult to remove the heat sink fan!

 

[Bill_Bright]

Arctic Silver 5 7 years after application was still working fine on 939 system, also was fused so hard it was difficult to remove the heat sink fan!

Right! Note this is why, if you really need to remove the heatsink, it is recommended you run the computer a few seconds to warm the TIM up, then gently apply back and forth twisting actions to break it loose. That is, don't start yanking on it when cold.

 

[peche]

the TIM does NOT need to be replaced just because years have passed - even if it dries out!

i have my mind full of f*cks.... sorry for that but explain me this sir....

 

[MrGenius]

i have my mind full of f*cks.... sorry for that but explain me this sir....

It's really simple actually. As long as there's no air, wet or dry does not matter. Nothing in TIM expires with time. Solvents may evaporate from it if exposed to heat and/or air, rendering it "less" useful for effective application. And oils may separate from solids, even if left sealed in long-term storage, but they can usually be remixed and used as normal if that happens.

 

[peche]

let me figure out something…

TIM dries out, solvents, oil pigments and many more craps start to degrades, for long times… so … there is no need to replace it, it just will work for miracle…even when pigments, oils and ingredients are degrading, drying or already gone…

I completely understand what's made for, to help as a bridge between CPU's I.H.S. and fill out microscopic holes, valleys and imperfections between 2 surface that aren't 100% flat, so thermal interface material is made for help heat got fully transferred and preventing heat gaps on already counted imperfections… so by the time and years pass by, all thermal shits are degrading, because several facts and issues such as air contact, temps up and down, thermal cycles like normal PC use or extreme and insane use, all of this an many more things affects TIM performance, in positive and negative side, but the fact here is that paste is getting degraded day by day so time really matters,

some TIM may last more than other that’s another important fact, but time, use and also application method and quantity or amount of paste used are critical facts in the process,

I'm not telling her that paste may be replaced pretty often, but it has to be some day, to keep cooling performance at its finest,

it's OK to say that old TIM will work fine, but how fine is working?

how do you know that old paste on several devices is not affecting performance?

I know that old paste can keep the work going… but I do not agree on keep using the same old paste.

 

[MrGenius]

It's hard to say it better than has already been said. I believe in leaving it be forever, if it's still working...why fix it? How long it's been there, or how "degraded" it might be, doesn't concern me. It's actually far more stable over time/while in use than you might realize. It's only worth replacing if you want to upgrade to a higher quality TIM, and/or if you assume it wasn't properly applied(and you think you can apply TIM better).

 

[NTM2003]

I have had it on my PC for a day now and it runs cool at 28-31c so seems to be fine

 

[Bill_Bright]

I don't see where all this cussing and obscenities help keep this discussion professional.

i have my mind full of f*cks.... sorry for that but explain me this sir....

I explained it in post #12 above. What are you not understanding?

The idea behind the TIM is to displace any air that may be trapped between the mating surfaces. Air is an insulator - you don't want an insulator there - you want something that conducts the heat. The ceramics or silver alloys (depending on formulas) in the TIM is what conducts the heat. Ceramics and silver alloys do not degrade or evaporate over time. They remain regardless what the other materials do so they are still doing their thing - that is, not allowing the insulating air to take their place.

Students of electronics are taught this in school. If you are not a formally trained electronics technician or EE, then this is not something you would necessarily know. And sadly, much mis-information has been posted by some who don't know what they are talking about - and then those falsehoods are spread and spread again until many believe they are true.

If you still refuse to accept this, look it up! Show us on the websites of your favorite TIM where they recommend regular replacement. Show us where they state their product looses effectiveness in x number years.

TIM is not like paint or other materials that are exposed to UV from the sun, or the harsh elements of the weather.

how do you know that old paste on several devices is not affecting performance?

What? Because the computer is still working! And the computer is stable and the temps are still good. Because as an electronics technician for 45 years, I have seen very old electronics chugging along just fine with old TIM. Because silver and ceramic materials do not lose their heat transfer properties over time just because the materials that make the silver and ceramics spreadable dry out.

I say again, if you refuse to accept this, look it up! Then show us!

It's hard to say it better than has already been said. I believe in leaving it be forever, if it's still working...why fix it? How long it's been there, or how "degraded" it might be, doesn't concern me. It's actually far more stable over time/while in use than you might realize. It's only worth replacing if you want to upgrade to a higher quality TIM, and/or if you assume it wasn't properly applied(and you think you can apply TIM better).

Right! And you need to replace it if the HSF was removed for any reason - such as before transporting the PC.

If you have seen temps rise over time, it is more likely because the fan is not spinning as fast as it did when new - which typically happens as bearings go through their natural wear and tear aging process. Other reasons are the ambient (room) temps rise. Voltage/current changes occur. And unless you actually wash the heatsink, grime, dust, skin oils and smoke particles from the kitchen (if not tobacco) will coat the heatsink (and everything that is exposed to the air too) and that also affects heat transfer efficiency.

 

[NTM2003]

I'm getting new thermal paste tomorrow so I be applying that tomorrow

 

[Bill_Bright]

I'm getting new thermal paste tomorrow so I be applying that tomorrow

Why? You just said above you are getting 28-31C temps. That is nothing short of outstanding! Understand you risk destroying your CPU, RAM and other sensitive devices from ESD and mishandling every time you reach inside your case. Why risk it when there is absolutely no need, or benefit?

 

[NTM2003]

So then it should be fine when iget my cooler in next month

 

[64K]

So then it should be fine when iget my cooler in next month

It will be fine with the temps that you are running until you get your new cooler next month. Be sure to clean off all of the TIM from your CPU before applying new TIM. You can use rubbing alcohol and coffee filters since they are lint free. I use a 2 stage cleaning kit from Arctic Cooling.

 

[NTM2003]

I'm having a PC shop to install it for me