Can you stack thermal pads to achieve thicker layers? Thermal Grizzly Minus Pad Pro Review and an astonishing finding | Practice

1 - Introduction and Overview 2 - Are 2 mm really 2 mm? 3 - Bulk Thermal Conductivity and Contact Resistances 4 - Thermal Resistance and Effective Thermal Conductivity 5 - Real Temperature Differences 6 - Summary and Conclusion

I am often asked whether it is permissible or even sensible to stack thermal pads if the exact thickness is not available and you don’t want to use thermal putty. This is exactly what I would like to answer today, because this issue is far less critical than it is often made out to be. In fact, the targeted stacking of pads can even be a very elegant solution to cover almost any situation with just a few standard thicknesses. If you know what you are getting into and what you need to consider.

In principle, pads with a thickness of 0.5 mm and 2.0 mm are already sufficient to bridge almost all conceivable height differences on a heat sink or memory bank using a simple modular system. So if you don’t want to stock a large selection of thicknesses, this combination works surprisingly well. Of course, you should keep a few subtleties in mind, such as the fact that even within a model series, pads can have noticeably different viscosities depending on their thickness. The thicker a pad, the softer it is in many cases. The dimensions are also subject to certain manufacturing tolerances, which can be particularly noticeable in precisely fitting applications.

Today’s test will not only substantiate this theory in practice, but will also reveal a few surprising findings that even surprised me in their clarity. Incidentally, it is not without reason that I am using the Minus Pad Pro instead of the Advance from Thermal Grizzly for this test. These pads do not require any zinc oxide at all and offer a perfectly acceptable compromise between mechanical stability and thermal performance, including decent durability. Their balanced hardness makes stacking much easier, as they neither deform too much nor are too unruly or brittle and tear quickly. This makes them ideal for practical tests where both user safety and reproducible results are paramount.

The problem of fragmentation

Modern graphics cards in particular show how diverse and at the same time confusing the use of thermal pads can be. Often, several different pad thicknesses are installed on a card, depending on which components are to be brought into contact with the heat sink or backplate. Typically, a different pad thickness is found between the main heat sink and the GDDR memory modules than for the voltage converters or the coils of the VRM section.

In addition, further pads are usually used on the rear of the PCB, which are located between the PCB and the backplate and also have to bridge height differences there. In practice, this often means that up to four different pad thicknesses are installed on a single graphics card. The exact values vary depending on the model and manufacturer, but the fact remains: Anyone who wants to maintain or upgrade such cards is faced with a veritable puzzle of thicknesses and materials. A modular approach with a few standard thicknesses and possibly stacked pads can not only help to save costs here, but also make handling much easier.

Separate correctly and only then stack!

When working with heat conducting pads, a certain processing sequence has proven itself to ensure clean edges and exact dimensions. First, I cut longer strips to the desired width while the protective film is still attached to both sides of the pad. This provides the necessary stability when cutting and prevents the material from warping too much during the first cut or sticking to the cutting pad. Only then do I remove the protective film and cut the pads to their final length, i.e. to their actual individual size.

The subsequent stacking only takes place at the very end. If you were to stack several layers beforehand and then cut them, the increased pressure would very quickly lead to deformations, shifted edges or slanted cutting lines. The resulting burrs or protrusions have a negative effect on the thermal contact and often mean that the pads can no longer be laid flat. A scalpel is the tool of choice in this context. It enables precise, smooth cuts without exerting too much pressure on the material. This is particularly important with softer pad types, as otherwise the material will deform or tear in an uncontrolled manner. A clean cut not only ensures a better appearance, but above all ensures even contact pressure and therefore reliable heat transfer.

When cutting heat conducting pads, it is essential to use the right base. Wooden cutting boards are extremely unsuitable here, even if they may seem practical at first. Wood has a porous surface and can absorb fine particles, fibers or residues from previous work. When cutting the pads, such particles can easily detach from the surface and press into the pad material or stick to its surface. Such inclusions are not only visually unclean, but can also impair the thermal conductivity of the pads, especially if they are trapped between the pad and the contact surface. With stacked pads in particular, every little unevenness disturbs the flatness and can lead to air gaps or uneven contact pressure. I therefore only use smooth, non-absorbent cutting pads made of plastic or glass. These can be cleaned without leaving any residue and provide a hard, flat surface, which is essential for precise cuts.

In combination with a scalpel, clean, sharp cuts can be made without the risk of creating impurities or inclusions. So much for the introduction, because now it’s time to get down to business! Turn the page please!

Thermal Grizzly Minus Pad Pro, 100x100x0.5mm, 1 Stück (TG-MP-P-100-100-05)

	Lagernd im Außenlager, Lieferung 2-3 WerktageStand: 23.12.25 08:09	29,85 €*Stand: 23.12.25 08:11
	Auf Lager	29,90 €*Stand: 23.12.25 08:10
	Lager Lieferant: vorrätig, 2-6 Werktage	29,90 €*Stand: 23.12.25 07:51

*Alle Preise inkl. gesetzl. MwSt zzgl. Versandkosten und ggf. Nachnahmegebühren, wenn nicht anders beschriebenmit freundlicher Unterstützung von geizhals.de

Thermal Grizzly Minus Pad Pro, 100x100x1mm, 1 Stück (TG-MP-P-100-100-10)

	Lagernd im Außenlager, Lieferung 2-3 WerktageStand: 23.12.25 08:09	29,85 €*Stand: 23.12.25 08:11
	Versandbereit: Lieferzeit 8-10 Werktage	29,90 €*Stand: 23.12.25 08:05
	Nicht lagernd, ab Bestellung versandfertig in 7-11 Werktagen	29,90 €*Stand: 23.12.25 08:10

*Alle Preise inkl. gesetzl. MwSt zzgl. Versandkosten und ggf. Nachnahmegebühren, wenn nicht anders beschriebenmit freundlicher Unterstützung von geizhals.de

Thermal Grizzly Minus Pad Pro, 100x100x1.5mm, 1 Stück (TG-MP-P-100-100-15)

	Lagernd im Außenlager, Lieferung 2-3 WerktageStand: 23.12.25 08:09	34,34 €*Stand: 23.12.25 08:11
	Bestellware - 9-11 Tage Lieferzeit	34,39 €*Stand: 23.12.25 07:43
	1-3 Werktage	34,90 €*Stand: 23.12.25 07:05

*Alle Preise inkl. gesetzl. MwSt zzgl. Versandkosten und ggf. Nachnahmegebühren, wenn nicht anders beschriebenmit freundlicher Unterstützung von geizhals.de