Thermal Grizzly Deltamate GPU Block Lowers ROG Astral RTX 5080 Temperature by Almost 20°C, According to Der8auer’s Demonstration

The Deltamate GPU block is an impressive cooling solution designed for high-end enthusiasts willing to invest over $600 in advanced thermal technology.

Der8auer Showcases the Superior Cooling Capabilities of the Deltamate GPU Block for ROG Astral RTX 5080

ASUS’s ROG Astral RTX 5080 GPU is positioned within the premium performance segment, yet its factory cooler may not meet the expectations of serious gamers and overclockers. If you own this model and seek enhanced cooling options, consider the Deltamate GPU water block, touted by Der8auer as “The Most Ambitious GPU Water Block”ever produced by Thermal Grizzly.

The Alphacool DeltaMate ROG Astral RTX 5080 graphics card block features a transparent liquid cooling design with blue visible channels.

In his latest video demonstration, Der8auer revealed the thermal performance improvements of the Astral RTX 5080 when equipped with the Deltamate block. This custom water block, designed specifically for the Astral RTX 5080, features a striking real-glass window encased in a black anodized aluminum shell. Despite its seemingly simple appearance, achieving a smooth finish on the water block was a significant challenge and a key factor in its premium pricing.

A screenshot shows TechPowerUp GPU-Z monitoring an ASUS RTX 5080 ASTRAL OC running at a GPU clock of 2452.0 MHz and a temperature of 71.0°C with a FurMark test. — Temperatures recorded with the stock cooler; Credit: Der8auer

According to Der8auer’s tests, the Deltamate significantly reduces both GPU and VRAM temperatures. The stock cooler left the ROG Astral RTX 5080 running quite hot, registering temperatures around 70°C under full load during FurMark stress tests, and VRAM temperatures peaked at 64-66°C. In contrast, when fitted with the Deltamate, the GPU maintained extraordinary thermal performance.

The GPU-Z interface shows the NVIDIA GeForce RTX 5080 at a GPU clock of 2497.0 MHz and a memory clock of 1875.1 MHz, achieving '274 FPS' on a FurMark demo. — Temperatures observed with the Deltamate installed; Credit: Der8auer

The Deltamate exhibited remarkable idle temperatures, with the GPU chip hovering around 25°C and the memory close to 36°C. Under a sustained stress test exceeding ten minutes with FurMark, the GPU temperature barely exceeded 49°C, while the VRAM temperature was even lower, around 44°C. This sharp contrast to the performance of the stock cooler underscores the effective design of the Deltamate.

The Deltamate GPU block for the ASUS ROG Astral GeForce RTX 5080 priced at $643.38, showcasing a Schott BOROFLOAT® glass window.

Constructed with a large copper cooler, the Deltamate features a dual-cold plate system, with the VRAM cold plate alone weighing over 900 grams. While this impressive cooling technology carries a hefty price tag of $643.38—nearly 50% of the current MSRP for the GeForce RTX 5080—enthusiasts must balance cost with performance. The current market price for the Astral RTX 5080 is about $1, 900 on platforms like Amazon and Newegg, bringing the total investment with the Deltamate cooler to approximately $2, 500.

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