Buying Guide
The Best Long-Lasting Thermal Paste
Five thermal pastes ranked on tube size and rated service life, where the MX-4 has the longest rated service life; the GC5 is the cheapest route in.
By The PC Journal editorial team
12 min read5 products evaluated
Pastes that resist pump-out and drying keep temperatures steady for years. Every pick states a service life or resistance to pump-out, drying or hardening, ordered by rated life.
We ranked these thermal pastes on amount, rated service life and compound using manufacturer specifications; where a maker leaves out rated service life, we say so rather than guess, since we have not benched them.
Quick Picks
Our 5 recommendations at a glance. Tap a pick for the full verdict.
Longest Rated Service Life
ARCTIC MX-4 (4g)
The longest rated service life here (up to 8 years).
Best for: Buyers who put rated service life first.
Our take Check price for ARCTIC MX-4 (4g) (opens in a new tab)
Also Consider
Noctua NT-H1 (3.5g)
Cleanup with a dry paper towel, no alcohol needed.
Best for: Buyers who want cleanup with a dry paper towel, no alcohol needed.
Our take Check price for Noctua NT-H1 (3.5g) (opens in a new tab)
Premium Pick
Noctua NT-H1 SW Edition (3.5g)
A rated usage time of up to five years on a CPU or GPU at the highest price in the group.
Best for: Buyers for whom price is not the deciding factor.
Our take Check price for Noctua NT-H1 SW Edition (3.5g) (opens in a new tab)
Lowest Price Here
Gelid Solutions GC5 (3.5g)
A lower price than the MX-4 and the rest when we checked.
Best for: Getting resistance to pump-out and drying under sustained load for the least money.
Our take Check price for Gelid Solutions GC5 (3.5g) (opens in a new tab)
Strong Alternative
ID-COOLING Frost X45 (4g)
A metal-free formula.
Best for: Buyers who want metal-free formula.
Our take Check price for ID-COOLING Frost X45 (4g) (opens in a new tab)
| Pick | Why it’s here | Best for | Price |
|---|---|---|---|
| The longest rated service life here (up to 8 years). | Buyers who put rated service life first. | Check price for ARCTIC MX-4 (4g) (opens in a new tab) |
| Cleanup with a dry paper towel, no alcohol needed. | Buyers who want cleanup with a dry paper towel, no alcohol needed. | Check price for Noctua NT-H1 (3.5g) (opens in a new tab) |
| A rated usage time of up to five years on a CPU or GPU at the highest price in the group. | Buyers for whom price is not the deciding factor. | Check price for Noctua NT-H1 SW Edition (3.5g) (opens in a new tab) |
| A lower price than the MX-4 and the rest when we checked. | Getting resistance to pump-out and drying under sustained load for the least money. | Check price for Gelid Solutions GC5 (3.5g) (opens in a new tab) |
| A metal-free formula. | Buyers who want metal-free formula. | Check price for ID-COOLING Frost X45 (4g) (opens in a new tab) |
Our Picks
Longest Rated Service Life1 of 5
ARCTIC MX-4 (4g) on Amazon (opens in a new tab)
MX-4 is the long-running default for good reason: a carbon-based, non-conductive paste that ARCTIC says lasts at least eight years once applied.
Best for
- Buyers who put rated service life first.
Skip if
- If budget leads, the GC5 was cheaper at our last price check.
Why we like it
It forgives a clumsy first application, and 4g covers several builds. On tube size it ties with the Frost X45 at 4g. On rated service life it leads this guide at up to 8 years, ahead of the NT-H1 (up to 5 years).
It also comes with a consistency ARCTIC pitches at first-time builders. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. It was priced above the GC5 and below the Frost X45 at the time of writing.
Key dimensions & specs
- Amount: 4g
- Rated service life: up to 8 years
- Compound: Carbon microparticle
- Electrically non-conductive: Yes
Pros
- 4g is enough for several applications
- Maker-rated for up to 8 years without reapplying
- Carbon microparticle formula
- Electrically non-conductive, so spills are harmless
Cons
- Costs more than the GC5 at the time of writing
Also Consider2 of 5
Noctua NT-H1 (3.5g) on Amazon (opens in a new tab)
NT-H1 needs no spreading and wipes off with a dry paper towel, which makes it one of the least fussy pastes to work with.
Best for
- Buyers who want cleanup with a dry paper towel, no alcohol needed.
Skip if
- Skip it if price comes first: the GC5 cost less when we checked.
Why we like it
Noctua rates it for up to five years on a CPU and about 15 applications on AM4 or LGA1700. It matches the NT-H1 SW and the GC5 on tube size (3.5g). It matches the NT-H1 SW on rated service life (up to 5 years).
It also comes with a recommended storage time of up to three years. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. Do not pre-spread it; let the cooler's mounting pressure distribute it. On price it sat fourth of 5, between the cheaper Frost X45 and the pricier NT-H1 SW, at the time of writing.
Key dimensions & specs
- Amount: 3.5g
- Rated service life: up to 5 years
- Applications per tube: About 3 to 20
- Application: No need to spread before mounting
Pros
- Maker-rated for up to 5 years without reapplying
- Cleanup with a dry paper towel, no alcohol needed
- Recommended storage time of up to three years
Cons
- Costs more than the GC5 at the time of writing
Premium Pick3 of 5
Noctua NT-H1 SW Edition (3.5g) on Amazon (opens in a new tab)
The SW Edition adds a spatula and three cleaning wipes to NT-H1, so it covers a full repaste from cleanup to spreading.
Best for
- Buyers for whom price is not the deciding factor.
Skip if
- Skip it if rated service life matters most to you; the MX-4 offers up to 8 years.
Why we like it
Noctua rates it for up to five years on a CPU or GPU. On tube size it ties with the NT-H1 and the GC5 at 3.5g. On rated service life it ties with the NT-H1 at up to 5 years.
It also offers a rated usage time of up to five years on a CPU or GPU and wipes that remove old paste without a separate cleaner. Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. At our last price check it topped the group, with the NT-H1 the nearest cheaper option. Rated service life is its weakest area, and the MX-4 covers it better at up to 8 years.
Key dimensions & specs
- Amount: 3.5g
- Rated service life: up to 5 years
- Applications per tube: About 3 to 20
- In the box: a spatula and three cleaning wipes
Pros
- Maker-rated for up to 5 years without reapplying
- Includes a spatula and three cleaning wipes
- Rated usage time of up to five years on a CPU or GPU
- Wipes that remove old paste without a separate cleaner
Cons
- Rated service life trails the MX-4 (up to 8 years)
- Costs more than the GC5 at the time of writing
Lowest Price Here4 of 5
Gelid Solutions GC5 (3.5g) on Amazon (opens in a new tab)
GC5 is Gelid's newest paste, a nano diamond-ceramic formula built to resist pump-out and drying under sustained load.
Best for
- Getting resistance to pump-out and drying under sustained load for the least money.
Skip if
- Skip it if tube size matters most to you; the MX-4 offers 4g.
Why we like it
It is non-conductive, non-curing and one of the cheapest 3.5g tubes here. It suits CPUs, GPUs, consoles and laptops. On tube size it ties with the NT-H1 and the NT-H1 SW at 3.5g.
Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. It cost the least of the 5 picks at the time of writing, with the MX-4 the next step up. It gives ground on tube size, where the MX-4 comes in at 4g.
Key dimensions & specs
- Amount: 3.5g
- Compound: Nano diamond-ceramic
- Electrically non-conductive: Yes
Pros
- Nano diamond-ceramic formula
- Electrically non-conductive, so spills are harmless
- Resistance to pump-out and drying under sustained load
- Non-curing, non-corrosive formula
Cons
- Tube size trails the MX-4 (4g)
- No published rated service life
Strong Alternative5 of 5
ID-COOLING Frost X45 (4g) on Amazon (opens in a new tab)
Frost X45 is a metal-free, non-conductive paste rated at 15.2 W/mK by ID-COOLING.
Best for
- Buyers who want metal-free formula.
Skip if
- The maker gives no rated service life, so look elsewhere if that figure decides it for you.
Why we like it
The 4g tube costs little and the maker says it resists drying, cracking and separation. It is metal-free and non-conductive, so overflow onto nearby parts is harmless. The 4g tube covers several builds.
Clean off old paste with isopropyl alcohol first, then apply a pea-sized dot or a thin line on the heatspreader; on large Intel chips an X or a line covers the longer die better. Its price falls between the MX-4 and the NT-H1, based on our last check. Buyers who need a confirmed rated service life should compare it with the MX-4, which offers up to 8 years.
Key dimensions & specs
- Amount: 4g
- Conductivity: 15.2 W/mK (maker's figure)
- Electrically non-conductive: Yes
Pros
- 4g is enough for several applications
- Maker-rated 15.2 W/mK conductivity
- Electrically non-conductive, so spills are harmless
- Metal-free formula
Cons
- No published rated service life
- Costs more than the GC5 at the time of writing
How We Chose
Each pick was assessed across 4 criteria weighted for real-world use.
- Durability
- We looked for maker claims on pump-out and long-term stability.
- Application
- We noted spreaders, wipes and the maker's application guidance.
- Safety
- We checked that each paste is listed as electrically non-conductive.
- Value
- We compared tube sizes and what comes in the box.
What to Look for in a Long-Lasting Thermal Paste
Key buying criteria so you get the right fit the first time.
Decide on tube size first
Among these picks, tube size runs from 3.5g on the GC5 to 4g on the MX-4. Pick the lowest figure that covers your use; the extra usually costs more than it returns.
Durability matters on hot CPUs
Some pastes pump out or dry over thermal cycles. Pastes built for long-term stability suit high-power CPUs you do not want to remount often.
Buy the amount you will use
One large CPU uses about 0.2g to 0.5g. A 1g tube covers a couple of builds; 4g or more suits regular remounts or several machines.
Check the rated service life
Some makers state how long the paste can stay on a CPU before it needs replacing, from about five years to eight. A longer rating suits a PC you won't open often.
GPU repasting needs more care
Graphics card dies are bare, so non-conductive paste and a thin, even layer matter more. Some pastes are sold specifically for direct-die use.
How to Choose a Long-Lasting Thermal Paste
By priority
| Priority | Consider | Why |
|---|---|---|
| Buyers who put rated service life first | MX-4 | The longest rated service life here (up to 8 years) |
| Buyers who want cleanup with a dry paper towel, no alcohol needed | NT-H1 | Cleanup with a dry paper towel, no alcohol needed |
| Buyers for whom price is not the deciding factor | NT-H1 SW | A rated usage time of up to five years on a CPU or GPU at the highest price in the group |
| Getting resistance to pump-out and drying under sustained load for the least money | GC5 | A lower price than the MX-4 and the rest when we checked |
| Buyers who want metal-free formula | Frost X45 | A metal-free formula |
Scroll sideways to see every column.
Key specs side by side
Figures as each maker states them.
| Paste | Amount | Rated service life | Compound | Applications per tube |
|---|---|---|---|---|
| MX-4 | 4g | up to 8 years | Carbon microparticle | Not listed |
| NT-H1 | 3.5g | up to 5 years | Not listed | About 3 to 20 |
| NT-H1 SW | 3.5g | up to 5 years | Not listed | About 3 to 20 |
| GC5 | 3.5g | Not listed | Nano diamond-ceramic | Not listed |
| Frost X45 | 4g | Not listed | Not listed | Not listed |
Scroll sideways to see every column.
Frequently Asked Questions
Which of these thermal pastes has the longest rated service life?
The MX-4, at up to 8 years. The NT-H1 follows at up to 5 years, while the NT-H1 SW has up to 5 years.
What is the least I can spend on one of these thermal pastes?
The GC5. It undercut the MX-4 when we checked, while the NT-H1 SW cost the most of the group.
Should I use liquid metal instead?
Only if you know the risks. It is electrically conductive and damages aluminium, so it is not a drop-in replacement.
How often should I replace thermal paste?
Only when you remove the cooler or temperatures rise over time. Many pastes last several years on a desktop CPU.
How do I remove old paste?
Wipe it off with a lint-free cloth and 90% or stronger isopropyl alcohol, then let it dry.
Bottom Line
Our first pick is the MX-4, chosen for the longest rated service life here (up to 8 years). Look at the NT-H1 for cleanup with a dry paper towel, no alcohol needed, the NT-H1 SW for a rated usage time of up to five years on a CPU or GPU at the highest price in the group and the GC5 for a lower price than the MX-4 and the rest when we checked if those matter more to you.
Hot, high-power CPUs cycle the paste hardest; check temperatures once a year.