Sorry I don’t remember what this series used for thermal transmission to the heat sink.
Most likely thermal paste not a pad and often it’s a bit thicker often 1.5 or 2.0 mm [product|IF145-798] as it is used to span a bit of distance which is common with VRAM chips used with dedicated GPU’s.
For CPU/GPU chips I strongly recommend thermal paste as you don’t want a distance between the heat source and the heat sink solution.