Watercool Heatkiller V Ultra liquid cooling block for RTX 5090 Palit & Gainward, ARGB, Nickel + Acrylic, black

Watercool Heatkiller V Ultra liquid cooling block for RTX 5090 Palit & Gainward, ARGB, Nickel + Acrylic, black is a full-cover GPU water block engineered to cool the GPU core, surrounding VRAM and VRM components on compatible Palit and Gainward RTX 5090 cards. The block combines a nickel-plated copper cold plate with an acrylic top in a black finish and integrated ARGB lighting. It is designed for installation in custom closed-loop or open custom watercooling loops to deliver lower operating temperatures and stable performance under sustained loads.

Advantages

The Heatkiller V Ultra provides direct contact cooling to the GPU die and adjacent memory and power circuitry, offering improved heat transfer compared with air cooling solutions. Its nickel-plated metal cold plate resists corrosion and optimizes thermal conductivity, while the acrylic top allows for a clean visual appearance and ARGB illumination. The full-cover design distributes coolant over critical components to reduce thermal hotspots and enable quieter system operation by reducing fan reliance.

Suitable for

• Custom watercooling builds using Palit or Gainward RTX 5090 graphics cards
• High-performance gaming and workstation systems seeking lower GPU temperatures
• Overclocking scenarios requiring efficient VRM and VRAM cooling
• Showcase PCs where ARGB lighting and a black acrylic top are desired

Key specifications

• Compatibility: Full-cover block for RTX 5090 models from Palit and Gainward
• Material: Nickel-plated metal cold plate and acrylic top with black finish
• Cooling coverage: GPU core, VRAM modules and VRM circuitry
• Lighting: Addressable RGB (ARGB) integrated illumination
• Mounting: Multi-point mounting hardware for secured contact to PCB
• Coolant ports: Standard G1/4" threaded fittings (user-supplied fittings required)

How to use

Prepare the graphics card by removing the original cooler according to the manufacturer’s disassembly instructions, clean the GPU die and contact surfaces with appropriate solvent, and apply a thin, even layer of thermal paste. Position the Heatkiller V Ultra over the PCB aligning the mounting holes, place the supplied thermal pads over VRAM and VRM areas as instructed, and install the mounting screws to obtain uniform pressure. Connect the ARGB header to a compatible controller or motherboard ARGB connector and attach coolant tubing using appropriate G1/4" fittings. Fill and leak-test the loop before powering the system.

Recommendations

Use compatible coolant and corrosion inhibitors, verify compatibility with your specific Palit or Gainward RTX 5090 PCB revision before installation, and perform a thorough leak test at low pressure. Tighten mounting hardware evenly to avoid PCB stress and monitor temperatures after first run to confirm correct contact and coolant flow.