Thermal paste fills the microscopic gaps between your CPU's heat spreader and the base of its cooler, so heat can pass from one to the other. Most coolers come with paste included or pre-applied, but if you are rebuilding a PC, moving a cooler or trying to bring down temperatures on an older system, buying a good tube is a small, cheap upgrade.
Forge PC has not tested thermal pastes. Our picks are based on Tom's Hardware's thermal paste testing, last updated on 26 June 2026, which covers 37 compounds on an AMD Ryzen 9 9950X with an Arctic Liquid Freezer III Pro 240 cooler, plus more than 90 earlier results on Intel Core i9 processors. Product details come from Tom's Hardware and the manufacturers. We have not listed UK prices, because we could not find a reliable UK price tracker for thermal paste; expect most tubes to cost far less than a CPU cooler.
Quick picks
Pick | Product | Type | Electrically conductive? |
|---|
Best overall | Thermal Grizzly Duronaut | Paste | No |
Runner-up | Arctic MX-6 | Paste | No |
Best value | ID-Cooling Frost X45 | Paste | No |
Best all-rounder for beginners | Noctua NT-H2 | Paste | No |
Best thermal pad | Thermal Grizzly Kryosheet | Graphene sheet | Yes (solid sheet) |
Experts only | Alphacool Eisfrost Extreme | Liquid metal | Yes |
1. Thermal Grizzly Duronaut: best overall
Tom's Hardware says Duronaut is "the best performing thermal paste we've tested, hands down". It is not electrically conductive, scores 4.5 out of 5 for ease of use in Tom's ratings, and is designed for long-term stability.
Thermal Grizzly says the name comes from "durability", and that its mix of silicone oil, aluminium microparticles and zinc oxide nanoparticles is designed to minimise the "pump-out effect", where paste is gradually squeezed out from under the cooler over time. It is sold in 2g, 6g and 30g sizes. Tom's only complaint is price: it costs more than rivals.
2. Arctic MX-6: runner-up
Arctic's MX-6 holds second place among traditional pastes in Tom's Hardware's benchmarks, and Tom's describes it as a favourite among PC enthusiasts. Arctic says MX-6 is "neither electrically conductive nor capacitive", contains no liquid metal, and is easy to apply even for beginners.
3. ID-Cooling Frost X45: best value
Tom's Hardware names the Frost X45 the best-performing paste it has tested on its air cooling system, and calls it the "hands-down winner if you're focused on value". It is non-conductive, and Tom's lists a thermal conductivity of 15.2W/mK.
4. Noctua NT-H2: best for beginners
Tom's Hardware's runner-up premium paste is unusual in having no listed "reasons to avoid". It is non-conductive, easy to use and clean up, and Tom's notes that the 3.5g tube includes three cleaning wipes, which makes it a good choice if you are replacing paste for the first time and need to clean the old paste off too.
5. Thermal Grizzly Kryosheet: best thermal pad
The Kryosheet is not a paste at all, but a graphene sheet that you place between the CPU and cooler. Tom's Hardware says it was the best thermal pad it had tested and that, on the Ryzen 9 9950X, it outperformed all traditional thermal pastes. It is clean to fit, needs no cleanup and can be reused.
There are caveats. Tom's notes that it costs more than paste, needs high mounting pressure to perform at its best, and is electrically conductive, although Tom's points out that it is a solid material. Tom's also points out that Kryosheet was a notable exception to the rule that pastes scale similarly on AMD and Intel CPUs, so results on your system may differ.
Tom's runner-up pad, Thermal Grizzly's PhaseSheet, is a phase-change material that melts under heat and pressure. It is reusable, but Tom's warns it needs an extensive burn-in period over multiple heating cycles before it reaches its best performance, so do not panic if temperatures look high at first.
Tom's Hardware's best liquid metal outperformed rival liquid metals in its testing, and Tom's recommends it for extreme overclocking. But liquid metal is electrically conductive and scores just 1 out of 5 for ease of use. Tom's warns that a single drop of conductive paste in the wrong place "can lead to a dead PC". Unless you know exactly what you are doing, stick with a non-conductive paste.
How to get the best results
Application and mounting matter most. Tom's Hardware says how you apply the paste and mount the cooler are "the two biggest factors" in performance, ahead of the choice of paste.
Check what came with your cooler. Many coolers include paste or have it pre-applied, as our best CPU cooler guide notes. You do not need to buy any for a first build unless you want to.
Clean off old paste fully before applying new paste, using alcohol and lint-free paper towels, as Tom's suggests for most of these pastes.
Avoid conductive compounds unless you have a specific reason to use them.
If your CPU runs hot, paste is rarely the only problem. Our guide to stopping a PC overheating covers dust, airflow and reseating the cooler, and our air cooler vs AIO comparison can help if your cooler is the real bottleneck.
Our verdict
For most people, Arctic MX-6 or Noctua NT-H2 is the best thermal paste to buy: both are non-conductive, easy to apply and near the top of Tom's Hardware's results. If you want the best tested performance and long-term stability, Thermal Grizzly Duronaut leads Tom's rankings, while ID-Cooling's Frost X45 is the value pick. The Thermal Grizzly Kryosheet is a clean, reusable alternative if your cooler mounts with high pressure. Avoid liquid metal unless you are an experienced overclocker. We have not tested these products ourselves; our picks are based on Tom's Hardware's testing and manufacturer information.
