Selecting the right thermal pad thickness for a GPU is one of the most common questions we get from engineers and technicians. Too thin, and the pad will not make contact between the component and heatsink. Too thick, and unnecessary thermal resistance is added that hurts cooling performance.
This guide maps the common GPU thermal pad thicknesses to their applications, explains how to measure the correct thickness, and covers what to do when the exact thickness is not available.
Common GPU Thermal Pad Thicknesses and Their Applications
Different components on a graphics card require different pad thicknesses because the gap between each component and the heatsink varies:
0.5 mm thermal pads are typically used on VRAM modules (GDDR6, GDDR6X) where the clearance between the memory chip and heatsink is minimal. The thin profile ensures good contact without excessive material. See our selection of 0.5 mm thermal pads for available materials.
1.0 mm thermal pads are the most common thickness for GPU core thermal pads. The GPU die typically has a 1.0 mm gap to the heatsink, though this varies by card manufacturer and cooler design. This is also a common VRAM thickness on some cards.
1.5 mm thermal pads bridge moderate gaps and are frequently used on VRM components where the power delivery section of the PCB sits slightly below the heatsink contact plane.
2.0 mm thermal pads fill larger gaps, particularly on VRMs with taller components or on cards with heatsinks that have significant height variation across the contact surface.
How to Measure the Correct GPU Thermal Pad Thickness
When replacing existing thermal pads, the simplest method is to measure the old pads with calipers before discarding them. However, compressed pads may be thinner than their original spec — thermal pads compress under heatsink pressure, so a pad that was originally 1.5 mm may measure 1.2 mm after years of use.
For new installations, follow these steps:
- Install the heatsink temporarily without thermal pads and measure the gap between each component and the heatsink contact surface
- Add 10-20% to the measured gap to account for compression — the pad should compress slightly when the heatsink is mounted, ensuring full contact
- Select the nearest standard thickness (0.5, 1.0, 1.5, 2.0 mm)
For more on measuring and specifying thermal pads, see our guide on finding the perfect fit.
What Happens If the GPU Thermal Pad Is Too Thick
An oversized thermal pad creates several problems:
- Poor heatsink contact — the heatsink may not make contact with the GPU core because the VRAM or VRM pads are too tall, leaving a gap at the core
- Excessive thermal resistance — heat must travel through more material, reducing cooling efficiency
- Mechanical stress — oversized pads put pressure on components when the heatsink is torqued down, which can crack BGA solder joints over time
What Happens If the GPU Thermal Pad Is Too Thin
A pad that is too thin will not bridge the gap:
- No contact — the pad floats between the component and heatsink without touching either surface, transferring almost no heat
- Air gaps — even if the pad touches, incomplete contact leaves air pockets that act as insulation
- Hot spots — without proper thermal transfer, the component temperature rises, potentially causing throttling or failure
Can GPU Thermal Pads Be Stacked?
When the exact thickness is not available, stacking thermal pads is a common workaround. Two 0.5 mm pads can approximate a 1.0 mm pad, for example. However, stacking introduces an additional interface between the two pads, which adds a small amount of thermal resistance. In practice, the performance impact is usually minimal, but for production applications, specifying the correct single-layer thickness is always preferable.
Tolerances on GPU Thermal Pad Thickness
Thermal pad materials have manufacturing tolerances on thickness. A “1.0 mm” pad may actually measure 0.95 mm or 1.05 mm. For most GPU applications, this tolerance is acceptable. For precision applications where the gap is tightly controlled, see our guide on tolerancing for thermal pads to understand what tolerances are achievable with die-cut parts.
Ordering Custom-Thickness GPU Thermal Pads
Many thermal pad materials are available in standard thicknesses (0.5, 1.0, 1.5, 2.0 mm), but some manufacturers offer intermediate thicknesses. NEDC can source materials in custom thicknesses and die-cut them to customer specifications. Request a quote with thickness requirements, and we will identify available materials that meet the specification.