US Department of Energy debunks Arctic Silver 5?

[FordGT90Concept]

It was 3-6C hotter than the thermal paste and those numbers won't improve with time. My guess is the AMD HSF isn't as flat as the AliExpress HSF; hence, 3C hotter.

 

[Grog6]

These "Curing cycles" don't happen if you apply it correctly.

The Cycle thing is the mobilization of the silver particles in response to heat.

If you do it right, in a thin layer, it will only improve 1 or 2 % over time.

You want a <2 mil thick layer, filling the AIR voids in the HS to CPU surface; if you're seeing 10% changes, you're doing it wrong.

I've done indium solder; it's barely better than AS5, and much harder to do.

 

[Vario]

I've been using AS5 for many years.

I have never noticed a big difference in temperatures between immediately after mounting and months or years later. I have read a lot of detractors comments about it being a downside to AS5 that it requires a curing period. I haven't noticed that issue. If it drops in temperature, it isn't really much.

Another comment people frequently mention is that it is conductive. It isn't.

I have also heard mention that it is that it is capactive and therefore dangerous for electronics. I haven't had any issue with electronics that have had AS5 applied to them. Perhaps it could destroy a device if it was inappropriately used.

I run AS5 on my CPUs and graphics cards, its given me more consistent results than any other paste. It lasts a long time for me too. I have a videocard I repasted in 2012 that is still working great.

If you look at comparisons of the typical non liquid metal pastes, you will find they are all very close together, typically differing by 1 to 3 degrees Celcius. For this reason, the temperature isn't the only criterion for me, I like a paste that is easy to apply, has consistent performance, and doesn't change over time. I also like the tackiness of AS5, the paste doesn't shift and dislodge or thin out.

To apply it, I put my finger in a stretched plastic baggy and then put a drop of it on the surface I wish to apply to. Then I spread it until the surface has a thin but uniform grey coating.

Today, playing GTA V for a couple hours, my 1060 with Arctic Mono Plus and AS5 paste didn't go over 50*C . My 8600K with PHTC14PE and AS5 paste didn't go over 60*C at 4.6 GHz / 4.3 uncore and ~1.18V. The room ambient is 27C.

https://www.tomshardware.com/reviews/thermal-paste-comparison,5108-9.html Note that the temperature range in the 'paste in a tube' products from the best observed to the worst observed is only about 4 degrees.

 

[FordGT90Concept]

You probably have air bubbles then. AS5 should improve over cycles as the silver sinters. It won't if there's air between the thermal surfaces. Pre-spreading it is the best way to make air pockets. Just because the temp diode doesn't have an air bubble directly over it doesn't mean there isn't one (or many) elsewhere. It's better to have too much and it squish over the edge of the heat spreader (it's non-conductive...won't damage anything) than not have enough or risk air bubbles.

 

[biffzinker]

(it's non-conductive...won't damage anything)

Hold up, Arctic Silver 5 is conductive, but a little bit over the edge of the heatspreader isn't going t ok hurt anything.

 

[FordGT90Concept]

Arctic Silver Incorporated - Arctic Silver 5

www.arcticsilver.com

Not Electrically Conductive:
Arctic Silver 5 was formulated to conduct heat, not electricity.

 

[biffzinker]

Arctic Silver Incorporated - Arctic Silver 5

www.arcticsilver.com

But it also says: (While much safer than electrically conductive silver and copper greases, Arctic Silver 5 should be kept away from electrical traces, pins, and leads. While it is not electrically conductive, the compound is very slightly capacitive and could potentially cause problems if it bridges two close-proximity electrical paths.)

 

[lexluthermiester]

Arctic Silver Incorporated - Arctic Silver 5

www.arcticsilver.com

But it also says: (While much safer than electrically conductive silver and copper greases, Arctic Silver 5 should be kept away from electrical traces, pins, and leads. While it is not electrically conductive, the compound is very slightly capacitive and could potentially cause problems if it bridges two close-proximity electrical paths.)

Actually, you're both right.

AS5 is capacitive under certain conditions, but it is not directly conductive.

Can't remember where I read the article, but there was a test conducted on an OC site in 2009 to see what AS5's properties are and it was shown to be an electrical insulator at room temperature but once heat was applied above a certain range it became capacitive at voltages above 6.7v. So as long as you don't get it on 12v trace lines you'd be fine. So some friends of mine and I decided to test this ourselves and discovered it was correct, though our test showed it didn't start having problems until it got to 8v. We believe it was because we didn't apply enough heat as it was limited to 90C. We did this on a Core2Quad that was OC'd and then on a hot plate. We concluded that AS5 is safe for all but the most careless bungling doofus.

So we need to keep it out of the hands of that guy from the Verge's PC build video... The Verge in general should avoid AS5.

 

[Basard]

I burned thru a tube of some Gelid in less than five applications... left me with a sour taste in my mouth, it basically costs 20x what AS5 costs. For such negligible difference in temp, I immediately went back to AS5.

 

[purecain]

those scores are interesting... I thought a few of the pastes were better than they actually are.

 

[lexluthermiester]

those scores are interesting... I thought a few of the pastes were better than they actually are.

Read through the thread before taking those results seriously. The testing methodology had a flaw of some sort.

 

[eidairaman1]

You probably have air bubbles then. AS5 should improve over cycles as the silver sinters. It won't if there's air between the thermal surfaces. Pre-spreading it is the best way to make air pockets. Just because the temp diode doesn't have an air bubble directly over it doesn't mean there isn't one (or many) elsewhere. It's better to have too much and it squish over the edge of the heat spreader (it's non-conductive...won't damage anything) than not have enough or risk air bubbles.

Have never had a problem using the recommended spread method, i set the sink down and press and twist twice and thats it

 

[lexluthermiester]

Have never had a problem using the recommended spread method, i set the sink down and press and twist twice and thats it

That's a good method.

 

[eidairaman1]

That's a good method.

But i spread the thermal compound on the ihs/die first.

I do that with all compounds

 

[FordGT90Concept]

those scores are interesting... I thought a few of the pastes were better than they actually are.

TL;DR: The test was for automotive thermal greases so they wanted good performance for cheap. The test didn't take into consideration sintering of silver until much, much later (which is what Arctic Silver 5 does). By the time they figured that out, they discovered permanently bonded solutions are the best...which isn't practical for home computers (requires heat and pressure on an industrial scale).

 

[eidairaman1]

TL;DR: The test was for automotive thermal greases so they wanted good performance for cheap. The test didn't take into consideration sintering of silver until much, much later (which is what Arctic Silver 5 does). By the time they figured that out, they discovered permanently bonded solutions are the best...which isn't practical for home computers (requires heat and pressure on an industrial scale).

Hence mixing AS5 and ASEpoxy 50/50 for semi permenant solution (requires normal mechanical force to break the bond)

 

[FordGT90Concept]

I was referring to Btech HM-2 which is a graphite thermoplastic:

HM-2 Highly Thermally Conductive Film | Btech Corp

HM-2 Highly Thermally Conductive Film btechcorp has invented and patented a process for aligning high density fibers through the thickness of a polymer matrix... up to 20 million fibers per square inch.

btechcorp.com

It's not an adhesive. After the heatsink has been bounded with HM-2, you're going to break the metal on either side before you break the thermoplastic bond.


Looking at Arctic Silver Epoxy, it has a much lower content of silver than Arctic Silver 5 does so I doubt it performs as well.

 

[plonk420]

Thats how I do it as well. Spread it with my finger in a plastic baggy.

whew, i thought i was the only one xD

 

[lexluthermiester]

Looking at Arctic Silver Epoxy, it has a much lower content of silver than Arctic Silver 5 does so I doubt it performs as well.

It does, I've used it in a number of applications over the years.

 

[RichF]

I think it's highly dubious that silver would be a useful component — because it tarnishes. I think it's there (in whatever minuscule amount) for marketing magic and to justify the price tag. Copper oxides are terrible thermal conductors when compared with pure copper and I have no reason to expect silver oxides will be any better.

 

[Grog6]

Considering that silver sulfide is very black, and AS5 is gray, I think you're incorrect.

Silicone oil is an amazing coating.

You are correct that most oxides are terrible conductors; but the only one I've ever seen used is beryllium oxide, which is what the white compound is made of.

They also used to make hard insulators for TO-3 and TO-220 transistors out of it.

 

[RichF]

Considering that silver sulfide is very black, and AS5 is gray, I think you're incorrect.

Yes the .00000001% of silver would affect the coloration in a strong way.

 

[Pheckphul]

<SNIP>

I've tested this personally, and it's not as good as AS5 claimed to be, but it was never below 8W/mK.

I can't explain it, but I think they're wrong, and probably didn't get it applied correctly.

<SNIP.

I didn't read both documents word-for-word, I just scanned through them. I didn't notice that they spent the 200 hours with cooling and heating cycles that AS5 supposedly needs to become optimally effective.

Just because it's DOE doesn't mean the guys know WTF they are doing. Worked at Lawrence Livermore National Laboratory for several years and came across plenty of lazy idiots.

 

[freeagent]

I've got nothing bad to say about AS5. I used it for nearly a decade and it was great. I would still be using it now, but I ran out and wanted to try something new.. glad I did because I don't see myself buying it anymore. Its still a good tim, just not as good as it used to be in these modern times.