Gelid says its new thermal pad beats thermal paste in performance, durability, and ease of application

Gelid HeatPhase Ultra
(Image credit: Gelid)

Hong Kong-based PC cases and cooling specialist Gelid has launched a new thermal pad product dubbed HeatPhase Ultra. As hinted at by the name, the company claims this thermal pad uses a phase-change material and offers the ultimate in thermal transfer efficiency between a processor and cooling block. Gelid has a lot of big claims for its HeatPhase Ultra, which it says is easier to apply, offers improved durability, and delivers better performance than traditional thermal pastes. 

It's difficult to understand how the HeatPhase Ultra thermal pad we see in the product images is a phase change material (PCM). According to our normal understanding of a PCM, it enjoys a very high latent heat capacity, which is absorbed or released when the material’s phase changes. A phase change might be from gas to liquid, from liquid to solid, or vice versa. How that works with this quite normal-looking pad, which claims to be “ultra-durable and non-curing… [and] no-bleeding,” is difficult to fathom from the product pages alone.

(Image credit: Gelid)

Moving along to other claims by Gelid, there's the HeatPhase Ultra's performance. Gelid has provided a performance chart, embedded below, which it says shows how well the HeatPhase Ultra thermal pad performs in direct comparison to a traditional thermal pad, and Gelid’s own GC Extreme thermal paste.

(Image credit: Gelid)

We have some experience with GC Extreme and it was the runner-up in the hotly contested best budget thermal paste category in our Best Thermal Paste for CPUs 2023 feature, which assessed 90 pastes.

In Gelid's testing with an AMD 7950X, the HeatPhase Ultra pad kept the CPU about 2 degrees Celsius cooler under load compared to GC Extreme paste (79 degrees Celsius). We think those results are actually very close and probably within the margin of error, but if HeatPhase Ultra is instead just an equal performer to GC Extreme, it is still a very valid alternative for the reasons outlined below.

Thermal pads can have inherent properties that are preferable to pastes. Gelid says the HeatPhase Ultra is effortless to apply or remove. Some images show a protective film being removed once the pad is in place on the cooler heatsink. Other thermal pad niceties such as a guaranteed evenness of application remain true here. Gelid also claims its new product is ultra-durable, with a long life during which it won’t cure, harden, or otherwise degrade. Moreover, the non-electrical conductive material is said to stay in place without spreading under pressure.

Swipe to scroll horizontally
HeatPhase Ultra specs

Density:

2.8+-0.2 g.cm³

Dimension:

40 x 40 x 0.2 mm (AMD-Version), 40 x 30 x 0.2 mm (Intel-Version)

Operating Temperature Range:

-50~125 ℃

Phase Transition Temperature:

45 ℃

Thermal Conductivity:

8.5 W/mk

Volume Resistivity:

1.0x10¹² Ω.cm

Gelid is now selling HeatPhase Ultra thermal pads pre-cut for modern Intel or AMD processors. In the table above you can see the pad dimensions for either CPU brand. The AMD pad costs $10, and the slightly smaller Intel pad is $9.50. It seems like you only get one pad for the price, but we’d still like to give this a test in the labs and see how it stacks up.

Mark Tyson
Freelance News Writer

Mark Tyson is a Freelance News Writer at Tom's Hardware US. He enjoys covering the full breadth of PC tech; from business and semiconductor design to products approaching the edge of reason.

  • Evaldino
    Great idea! Expensive, yes, but if independent tests confirm the data, I would take it. Because I simply hate playing with those tubes.
    Reply
  • hannibal
    I have used Thermal Grizzly thermal pads in CPU for years and I am very happy. Easy to install. You newer have to reapply new, because it last as long as the CPU last. And it is rather close to normal thermal paste considering the heat transfer (and much, much better than old thermal paste).
    Reply
  • drajitsh
    The doubt I have is not about the conductivity of the pad but the thickness. I too would really like an independent review
    Reply
  • hotaru.hino
    The specs seem close to Honeywell's PTM7950, which is already a community favorite. The only difference is Honeywell only sells this directly to system builders and you have to find resellers to get some which may be sketch.

    But otherwise the idea of a "phase change" thermal pad is fairly old. I remember my AMD Athlon XP had a similar thing on it.
    Reply
  • edzieba
    The 'phase change' could be a lot more boring: a thermal paste that is solid at room temperature for application, then melts to a liquid (or more accurately the particulate carrier does) to flow under operating temperature and cooler mounting pressures to seat the two surfaces more closely as a traditionally applied thermal paste would. The 45°C transition temperature backs this up.
    Makes it ineligible for applications that need the dimensional stability of a traditional thermal pad, but ideal for CPUs and other applications where the HSF is mounted via pressure rather than hard-mounted.
    Reply
  • bit_user
    hotaru.hino said:
    But otherwise the idea of a "phase change" thermal pad is fairly old. I remember my AMD Athlon XP had a similar thing on it.
    Then please explain it to us.

    edzieba said:
    The 'phase change' could be a lot more boring: a thermal paste that is solid at room temperature for application, then melts to a liquid (or more accurately the particulate carrier does) to flow under operating temperature and cooler mounting pressures to seat the two surfaces more closely as a traditionally applied thermal paste would.
    This is somewhat at odds with their assertion that it'll stay in place and won't spread under pressure.
    Reply
  • hotaru.hino
    bit_user said:
    Then please explain it to us.
    Explain what? How it works? @edzieba already did that.
    Reply
  • bit_user
    hotaru.hino said:
    Explain what? How it works? @edzieba already did that.
    Nah, that doesn't make sense.

    To have value in a stable system, phase-change cooling requires convection. It needs to be elevated to a higher-energy state at a hot spot, then migrate to a cooler location and transition back downward. Finally, it needs to be able to return back to the hot spot so the cycle can continue.

    That's what going on inside heat pipes, vapor chambers, and freon-based refrigerators & air conditioning units.
    Reply
  • thestryker
    hotaru.hino said:
    The specs seem close to Honeywell's PTM7950, which is already a community favorite. The only difference is Honeywell only sells this directly to system builders and you have to find resellers to get some which may be sketch.
    Definitely seems to be, and you can already get these sold by Thermalright in the $5-6 range via Amazon (at least in the US).
    Reply
  • CorrOzi0n_s0cZ
    This is simply a more readily available to the general consumer alternative to PTM 7950 and isn't a new technology or concept. Thermalright also has had a PCM solution out for the public for a while now. It's a thermal pad that changes to liquid after reaching a target temperature, after multiple thermal cycles converting it from solid to liquid while being under the mounting pressure of the CPU or GPU cooler the end result is a more uniform bond between the die and the heatsink versus what can be achieved with traditional thermal paste. These solutions result in a significantly longer lasting (the lifetime of the device) and more performant thermal solution that doesn't suffer from pump out due to its ability to easily convert from a solid into a liquid; These characteristics make it the perfect option for not only laptop CPU's and GPU's but also their desktop counterparts and pretty much anything in between that will regularly produce enough heat to cause the material to phase change. The next closest thing in cooling performance is liquid metal.
    Reply