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Alphacool Apex Thermal Pad Soft 18W/mK vs Phobya Thermal Pad Ultra 5W/mK: Comparison

Alphacool Apex Thermal Pad Soft 18W/mK vs Phobya Thermal Pad Ultra 5W/mK viscosity compared

The first real difference is viscosity: Alphacool Apex Thermal Pad Soft 18W/mK 0 Pa-s against Phobya Thermal Pad Ultra 5W/mK 4 Pa-s. They differ on recommended use too, High-end CPU/GPU on the Alphacool Apex Thermal Pad Soft 18W/mK versus Mainstream CPU/GPU; Phobya also markets it for VRAM, VRM,... on the Phobya Thermal Pad Ultra 5W/mK.

Alphacool Apex Thermal Pad Soft 18W/mK vs Phobya Thermal Pad Ultra 5W/mK: 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 is equally the pick for builds needing a documented electrical safety spec sheet (volume resistance, dielectric breakdown) rather than a generic non-conductive claim. Avoid it for buyers who specifically want Eisschicht's softer, more paste-like conforming fit for delicate uneven surfaces. it is not built for buyers wanting Phobya's higher-conductivity Thermal Pad XT line instead. It also earns its place with VRAM, VRM, and mainboard chipset cooling needing a compressible pad to bridge height differences up to 4mm. It is not the one for CPU IHS-to-cooler contact where a conventional paste offers thinner bond lines. 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 Phobya Thermal Pad Ultra 5W/mK (5.8/10): A small single-piece pad with modest conductivity, a niche fit for specific gap sizes.

Where the two are identical

Where they agree, they agree completely, electrical conductivity and paste segment included, so the decision does not turn on any of those.

Alphacool Apex Thermal Pad Soft 18W/mK (Silicone-Based Pad/Non-Conductive/High-end CPU/GPU)
Alphacool
Alphacool Apex Thermal Pad Soft 18W/mK
Phobya Thermal Pad Ultra 5W/mK (Pad/Non-Conductive/15x15x4mm)
Phobya
Phobya Thermal Pad Ultra 5W/mK

Specs and benchmarks

  • Brand

    Alphacool Apex Thermal Pad Soft 18W/mK
    Alphacool
    Phobya Thermal Pad Ultra 5W/mK
    Phobya

  • Model

    Alphacool Apex Thermal Pad Soft 18W/mK
    Alphacool Apex Thermal Pad Soft 18W/mK
    Phobya Thermal Pad Ultra 5W/mK
    Phobya Thermal Pad Ultra 5W/mk

  • Electrical Conductivity

    Alphacool Apex Thermal Pad Soft 18W/mK
    Insulating
    Phobya Thermal Pad Ultra 5W/mK
    Insulating

  • Package Size

    Alphacool Apex Thermal Pad Soft 18W/mK
    120 x 20 x 1.5mm sheet
    Phobya Thermal Pad Ultra 5W/mK
    15 x 15 x 4mm, sold as a single piece; also available in other sizes up to 120x20mm strips

  • Recommended Use

    Alphacool Apex Thermal Pad Soft 18W/mK
    High-end CPU/GPU
    Phobya Thermal Pad Ultra 5W/mK
    Mainstream CPU/GPU; Phobya also markets it for VRAM, VRM, and North/Southbridge cooling

  • Viscosity

    Alphacool Apex Thermal Pad Soft 18W/mK
    0 Pa-s
    Phobya Thermal Pad Ultra 5W/mK
    4 Pa-s

  • Paste Segment

    Alphacool Apex Thermal Pad Soft 18W/mK
    Pad
    Phobya Thermal Pad Ultra 5W/mK
    Pad

    Which one should you pick?

    Choose Alphacool Apex Thermal Pad Soft 18W/mK if you already have it on hand or find it at a lower price.

    Choose Phobya Thermal Pad Ultra 5W/mK if you already have it on hand or find it at a lower price.

    Price comparison

    RetailerAlphacool Apex Thermal Pad Soft 18W/mKPhobya Thermal Pad Ultra 5W/mK
    Alphacool Shop (EU)View on Alphacool Shop (EU)
    Performance-PCsView on Performance-PCs
    NeweggView on Newegg

    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.

    Phobya Thermal Pad Ultra 5W/mK

    5.8 / 10 Expert Rating

    A small single-piece pad with modest conductivity, a niche fit for specific gap sizes.

    More comparisons in Thermal Paste