Consumercarts is reader-supported. Learn more
Alphacool Apex Thermal Pad Soft 18W/mK vs PrimoChill Ultra Extreme XR-m Thermal Pad: Comparison
Alphacool Apex Thermal Pad Soft 18W/mK vs PrimoChill Ultra Extreme XR-m Thermal Pad: the thermal conductivity difference
These two are close on paper, and thermal conductivity is the only measure that separates them at all: Alphacool Apex Thermal Pad Soft 18W/mK 17.8 W/mK against PrimoChill Ultra Extreme XR-m Thermal Pad 17.0 W/mK. Recommended use is not the same on both, High-end CPU/GPU on the Alphacool Apex Thermal Pad Soft 18W/mK versus GPU VRM/MOSFET Cooling, Case-Mod Builds on the PrimoChill Ultra Extreme XR-m Thermal Pad. They differ on conductivity source too, https://shop.alphacool.com/en/shop/thermal-conductant/thermal-pads/waem-alphacool-apex-thermal-pad-soft-18w/mk-120x20x1mm on the Alphacool Apex Thermal Pad Soft 18W/mK versus https://www.primochill.com/products/primochill-ultra-extreme-thermal-pad-100-x-15-x-1-5-thermal-conductivity-17-0-w-mk on the PrimoChill Ultra Extreme XR-m Thermal Pad.
Alphacool Apex Thermal Pad Soft 18W/mK vs PrimoChill Ultra Extreme XR-m Thermal Pad: which one fits your build
Take the Alphacool Apex Thermal Pad Soft 18W/mK for high-end CPU/GPU, VRM/MOSFET, and memory-module cooling wanting the highest independently-measured W/mK figure among this catalog's pads. It also earns its place with builds needing a documented electrical safety spec sheet (volume resistance, dielectric breakdown) rather than a generic non-conductive claim. It is the wrong buy for buyers who specifically want Eisschicht's softer, more paste-like conforming fit for delicate uneven surfaces. it is not the pick for standard CPU IHS-to-cooler applications where a conventional paste is simpler. The same goes for GPU VRM/MOSFET cooling and case-mod builds needing a cuttable, shapeable thermal pad. Avoid it for anyone needing a spreadable liquid compound rather than a solid cut-to-size sheet. Our rating of the Alphacool Apex Thermal Pad Soft 18W/mK (6.8/10): A soft, high-conductivity pad aimed at high-end builds, though it lacks the independent review base of the paste side of Alphacool's lineup. Our rating of the PrimoChill Ultra Extreme XR-m Thermal Pad (6.9/10): A cuttable high-conductivity sheet aimed at GPU VRM and case-mod cooling, from a brand known for water-cooling components.
Where the two are identical
The common ground is wider than the gap: compound type, electrical conductivity and paste segment are identical here.
Specs and benchmarks
Brand
- Alphacool Apex Thermal Pad Soft 18W/mK
- Alphacool
- PrimoChill Ultra Extreme XR-m Thermal Pad
- PrimoChill
Compound Type
- Alphacool Apex Thermal Pad Soft 18W/mK
- Silicone-Based Pad
- PrimoChill Ultra Extreme XR-m Thermal Pad
- Silicone-Based Pad
Model
- Alphacool Apex Thermal Pad Soft 18W/mK
- Alphacool Apex Thermal Pad Soft 18W/mK
- PrimoChill Ultra Extreme XR-m Thermal Pad
- PrimoChill Ultra Extreme XR-m Thermal Pad
Thermal Conductivity
- Alphacool Apex Thermal Pad Soft 18W/mK
- 17.8 W/mK (ASTM D5470)Best
- PrimoChill Ultra Extreme XR-m Thermal Pad
- 17.0 W/mK
Electrical Conductivity
- Alphacool Apex Thermal Pad Soft 18W/mK
- Insulating
- PrimoChill Ultra Extreme XR-m Thermal Pad
- Insulating
Package Size
- Alphacool Apex Thermal Pad Soft 18W/mK
- 120 x 20 x 1.5mm sheet
- PrimoChill Ultra Extreme XR-m Thermal Pad
- 60x50mm sheets, multiple thicknesses
Recommended Use
- Alphacool Apex Thermal Pad Soft 18W/mK
- High-end CPU/GPU
- PrimoChill Ultra Extreme XR-m Thermal Pad
- GPU VRM/MOSFET Cooling, Case-Mod Builds
Conductivity Source
- Alphacool Apex Thermal Pad Soft 18W/mK
- https://shop.alphacool.com/en/shop/thermal-conductant/thermal-pads/waem-alphacool-apex-thermal-pad-soft-18w/mk-120x20x1mm
- PrimoChill Ultra Extreme XR-m Thermal Pad
- https://www.primochill.com/products/primochill-ultra-extreme-thermal-pad-100-x-15-x-1-5-thermal-conductivity-17-0-w-mk
Paste Segment
- Alphacool Apex Thermal Pad Soft 18W/mK
- Pad
- PrimoChill Ultra Extreme XR-m Thermal Pad
- Pad
Which one should you pick?
Choose Alphacool Apex Thermal Pad Soft 18W/mK if you want the higher thermal conductivity (17.8 W/mK (ASTM D5470) vs 17.0 W/mK).
Choose PrimoChill Ultra Extreme XR-m Thermal Pad if you already have it on hand or find it at a lower price.
Price comparison
| Retailer | Alphacool Apex Thermal Pad Soft 18W/mK | PrimoChill Ultra Extreme XR-m Thermal Pad |
|---|---|---|
| Alphacool Shop (EU) | View on Alphacool Shop (EU) |
Disclaimer: The price and specification of the given product may differ from the actual product. Please confirm on the retailer's website before buying.
Verdict
Alphacool Apex Thermal Pad Soft 18W/mK
6.8 / 10 Expert Rating
A soft, high-conductivity pad aimed at high-end builds, though it lacks the independent review base of the paste side of Alphacool's lineup.
PrimoChill Ultra Extreme XR-m Thermal Pad
6.9 / 10 Expert Rating
A cuttable high-conductivity sheet aimed at GPU VRM and case-mod cooling, from a brand known for water-cooling components.
More comparisons in Thermal Paste
- Alphacool Apex Thermal Pad Soft 18W/mK vs Noctua NT-H1
- Arctic MX-7 vs PrimoChill Ultra Extreme XR-m Thermal Pad
- Alphacool Apex Thermal Pad Soft 18W/mK vs Noctua NT-H2
- Alphacool Apex Thermal Pad Soft 18W/mK vs Honeywell PTM7950
- Alphacool Apex Thermal Pad Soft 18W/mK vs PCCooler EX90
- Alphacool Apex Thermal Pad Soft 18W/mK vs Thermal Grizzly KryoSheet