What Thermal Grizzly is claiming
The company says a composition optimized for improved thermal conductivity, plus a new carrier film, makes the Pro easier to handle. The carrier film peels away easily from both sides, which should significantly reduce the risk of tearing the sheet. Anyone who has wrestled with a flimsy thermal pad while holding a heatsink in the other hand will see why that matters.
The basics are:
- Material: a phase-change material (PCM) sheet. It is solid at room temperature, goes on easily, and liquefies during operation so it dissipates heat like thermal paste.
- Electrical behavior: It is electrically non-conductive. Thermal Grizzly names processors and graphics chips as the primary applications.
- Format: a single 40 × 40 mm sheet, model TG-PS-P-40-40, sold through Thermal Grizzly's own store.
How a phase-change sheet works, and why pump-out matters
Per Thermal Grizzly's announcement, the material is solid at room temperature and only begins to liquefy above 45 °C. In its liquid state it has very low viscosity and contracts again as it returns to a solid. The company says this mitigates pump-out.
Pump-out is the slow squeezing-out of paste. Thermal Grizzly's explanation is that silicon and copper expand at different rates, so the heat spreader and cooler base plate flex slightly under load. They flatten again as they cool. The paste is gradually pushed out from between the heat spreader and the cooler baseplate. The company says the effect is especially pronounced when a copper cooler is paired with a graphics chip.
Installation caveats
This is not a drop-in magic fix. Thermal Grizzly says it needs a high mounting force of roughly 300–400 N to distribute the liquefied material and form the thinnest possible layer. Coolers with weak or uneven mounting pressure may not suit it. Thermal Grizzly's announcement gives no compatibility list for specific cards or coolers, so check your cooler's mounting design before you strip anything down.
The Dutch site Techtesters adds two details from the manufacturer. The sheet reportedly reaches its maximum thermal conductivity only after about ten heat cycles above 60 °C. Thermal Grizzly also calls it more durable than traditional paste but less durable than its own KryoSheet. The original PhaseSheet PTM page carries the same ten-cycle guidance. Tech4Gamers' review of the original on an RTX 5080 reported that temperatures started about 5 °C higher but settled after five cycles. That is a result for the original sheet, not the Pro. Still, it suggests early temperatures on a fresh install may not reflect the final result.
The numbers, and how far to trust them
In a chart shared by Thermal Grizzly, using a 30 × 30 mm contact area, 300 N of mounting force and a 240 W heat load, the Pro recorded a temperature difference of 5.83 °C. That was the lowest of the materials tested. The others:
| Material | Reported temperature difference (lower is better) |
|---|---|
| PhaseSheet PTM Pro | 5.83 °C |
| KryoSheet | 6.13 °C |
| Duronaut Pro | 6.29 °C |
| Original PhaseSheet PTM | 6.36 °C |
The gap to the original is about half a degree in a lab fixture. This is Thermal Grizzly's own test, not independent testing. A bench TIM tester isolates the material in a way a real PC cannot. Real systems add cooler mounting variation, die size, heat density and fan curves. Expect a modest real-world gain at best. The practical appeal is probably handling and long-term stability rather than a dramatic temperature drop. As Techtroduce put it, independent testing is needed to establish how much of a temperature difference the revised material delivers in actual hardware.
Price
The Pro is sold directly from Thermal Grizzly's site in the 40×40 mm size at $23.28. The store lists that as $1.46 per 100 mm² and says prices include VAT but not shipping. Techtesters reports €19.90 in the German store, which shows regional pricing differs.
Tom's Hardware compares this with the original, which it says costs $13.92 for a larger 50 × 40 mm sheet. That original price was not confirmed against the current store page. If it's right, the Pro costs noticeably more for less area. A 40 × 40 mm sheet covers many CPU heat spreaders and GPU dies, but check the size you need before buying.
A claim to treat with caution
Tom's Hardware says the sheet is reusable and safe on components such as memory and storage. Thermal Grizzly's own product page is narrower. It says the sheet is electrically non-conductive and can be used in many areas, but names processors and graphics chips as the main use. Stick to the manufacturer's stated use unless you have a specific, verified reason to go further.
Bottom line
- What's new: a reformulated PCM sheet with a carrier film that peels from both sides.
- Who it's for: people repasting GPUs or CPUs who want less pump-out and a cleaner install.
- What to check first: your cooler's mounting pressure (about 300–400 N is recommended) and the sheet size you need.
- What to wait for: independent reviews on real CPUs and GPUs before paying the premium for a roughly half-degree lab gain.