Does Thermal Paste Expire?

lettuce · 9 Jun 2019 at 15:47

Have had some Arctic Silver 5 for about 8 years and am just wondering if it loses some of its ability to cool over time or even expires completely, the paste itself hasn't gone hard or watery and still looks like it did when first opened.

Also what is considered the best paste in 2019 still Thermal Grizzly Kryonau or Noctua NT-H1?

Jokester · 9 Jun 2019 at 16:03

Some are prone to separating, but it’s not something i’ve seen with AS5.

It’ll be in better condition than used TIM in a lot of cases.

doyll · 9 Jun 2019 at 17:37

As long as it pushes out of tube and is not too thick or separated as Jokester pointed out it is fine. Even separated is fine if you can mix it up again, but kinda hard to do unless in a squeeze tube and even then not easy.

Rroff · 9 Jun 2019 at 17:51

Unused tubes seem to hold up fine for around 10+ years - partially used ones seem to start separating a bit after 5 or so years but in my experience mix up again fine without any noticeable impact on performance. I tend to replace mine every few years though just to be sure. In theory AS5 shouldn't separate, etc. but in my experience it can happen.

On another note I see they've updated the datasheet (think I noticed it before but forgot about it) to recommend tinting as a practise when applying it - hand spreading with an edge then wiping off before then applying a line (or blob depending on CPU). Apparently is lessens the break in period with AS5. I guess this is due to reviewers giving it poor results because they can't be bothered to read the application notes and test it when it has reached optimal performance.

I'm going to go against the grain here and say I still highly recommend AS5 when applied properly it is very close to anything on the market and has better long term stability than most of the hyped up pastes.

Jokester · 9 Jun 2019 at 18:04

I still use AS5 as it's easy to use and I've never had anything that outperforms it by a reasonable amount, apart from Liquidmetal and it has other issues.

doyll · 9 Jun 2019 at 18:05

As Rroff said, tinting helps. If you have same TIM on mount now, all you need to do is wipe/rub off all the TIM, but do not use any cleaning agent. This way the CPU and cooler base have some residual of the TIM on them and this is supposed to help the spread from a dob or line when cooler is pressed down and mounted. In theory it makes sense, but in practice the difference (if any) is so little it can't be accurately measured.

lettuce · 9 Jun 2019 at 19:04

Thanks for the replies. Yeah ive used the same tube of AS5 for about 6-8 different builds (family & friends) over the 8 years or so ive had the paste, so has been open and used a few good times and not brand new never used stuff.

So if im want to reapply AS5 to my cpu its best advised not to clean the cpu with rubbing alcohol etc removing all traces of AC5 completely and instead just wipe if off with a cloth?

Rroff · 9 Jun 2019 at 19:07

lettuce said:
Thanks for the replies. Yeah ive used the same tube of AS5 for about 6-8 different builds (family & friends) over the 8 years or so ive had the paste, so has been open and used a few good times and not brand new never used stuff.

So if im want to reapply AS5 to my cpu its best advised not to clean the cpu with rubbing alcohol etc removing all traces of AC5 completely and instead just wipe if off with a cloth?

Clean it off properly if old stuff is on there - there are instructions in the AS5 datasheet for best practices.

doyll · 9 Jun 2019 at 19:21

lettuce said:
Thanks for the replies. Yeah ive used the same tube of AS5 for about 6-8 different builds (family & friends) over the 8 years or so ive had the paste, so has been open and used a few good times and not brand new never used stuff.

So if im want to reapply AS5 to my cpu its best advised not to clean the cpu with rubbing alcohol etc removing all traces of AC5 completely and instead just wipe if off with a cloth?

As long as it's wiped down to bare metal it will be fine. I use paper towel cut into about 2" squares and have waste basket with plastic bag in it close by. Wipe and put in waste basket until clean. That way none of the TIM gets onto things we don't want it on.

Meridian · 10 Jun 2019 at 18:00

I think my AS5 is actually older than that - about 10 years - and it works fine. You need to discard the first bit out of the nozzle, but only about 3-5mm worth.

FlyingScotsman · 17 Jun 2019 at 13:50

Yeah I have some AS5 which is 10 odd years old and did a mates build a few months back, no issues still the same as when it was new.

ricid · 18 Jun 2019 at 18:40

Thanks for this post, found some AS5 in a shoe box yesterday and was just wondering whether to chuck it.