Alphacool ES Geforce RTX 4090 Reference Design with Backplate (13395)

The Alphacool ES Geforce RTX 4090 Reference Design with Backplate is a GPU water block for Nvidia Geforce RTX 4090 graphics cards built on the Reference Design board, such as the Inno3D iCHILL X3. It belongs to Alphacool's Enterprise Series for the server rack: both ports sit at the back of the cooler, the top is carbon, and the black aluminum backplate is in the box. It is not compatible with Nvidia's Geforce RTX 4090 Founders Edition.

Properties

Fits

Geforce RTX 4090, Reference Design board

Cold plate

Chrome-plated copper

Top

Carbon

Ports

2 x G1/4, at the back

Backplate

Aluminum, black, included

Form factor

1.5U, not 1U compatible

Compatibility

Alphacool lists these cards for this block:

• Inno3D GeForce RTX 4090 iCHILL Black, 24GB GDDR6X (C4090-246XX-18330005)
• Inno3D GeForce RTX 4090 iCHILL Frostbite, 24GB GDDR6X (C4090-246XX-1833FB)
• Inno3D GeForce RTX 4090 iCHILL X3, 24GB GDDR6X (C40903-246XX-1833VA47)
• Inno3D GeForce RTX 4090 X3 OC, 24GB GDDR6X (N40903-246XX-18332989)
• KFA² GeForce RTX 4090 SG (1-Click OC), 24GB GDDR6X (49NXM5MD6DSK)

Attention: Alphacool warns that INNO3D uses two different PCB layouts. Check the serial number of your card: if it looks like 32-879-xxxx8xxxx, the card is not compatible with Alphacool's water blocks. The block was built for one PCB layout. Before ordering, compare your card and its PCB number with the pictures in Alphacool's GPU configurator, or look it up in its compatibility list for Nvidia cards. Alphacool's Core block for the same board is the Core Geforce RTX 4090 Reference Design with Backplate.

Built for the server rack

Alphacool developed the ES GPX Copper/Carbon water cooler for its Enterprise Series. The positioning of the connections is the reason: due to it, the hosing of the cooler in the server rack is significantly simplified. The top is made of carbon, which makes the water cooler lighter compared to Alphacool's Eisblocks with acetal or acrylic tops. The design is compact, and thanks to that only 1 slot is needed to mount the cooler in the rack instead of 1.5 slots as before. Alphacool counts this additional space saving as one more argument for using its ES graphics card water cooler. It also states that this cooler is not 1U compatible, and its data sheet gives the form factor as 1.5U.

Connections on the back

The water input and output have been moved to the back of the cooling block in order to save space in the width and height during installation. Alphacool says this makes hosing much easier. By its account it enables easy integration of the GPU cooler into the water circuit, even in the tightest server housings.

More performance

Alphacool says it manages to position the cooler as close as possible to the components to be cooled. The heat conducting pads used for this purpose are reduced to a thickness of 1 mm. The copper block was made as thin as possible (Alphacool speaks of the maximum possible reduction in thickness). The other step is the optimization of the water flow inside the cooler. According to Alphacool, both allow all important components such as GPU, voltage converters and VRAMs to be cooled by water much better and more effectively. All of this, it says, provides a significant increase in cooling performance.

Chrome-plated copper

From the base up, the cooler is made entirely of chrome-plated copper. Alphacool says a chrome plating is much harder than a nickel plating and therefore less sensitive to acids, scratches and damage. By its account that completely eliminates the risk of chipping that nickel plating carries. Additionally, Alphacool finds that chrome looks much more homogeneous and provides a shine that cannot be achieved by nickel. Chrome-plated coolers, it says, have previously only been used in the industrial sector, in areas where extreme influences act on the coolers.

Copper or aluminum

For all water-bearing parts Alphacool uses only copper. Its reason: copper has almost twice the thermal conductivity of aluminum and is therefore, in its words, clearly the better choice of material for water cooling. It adds that the chrome-plated copper base is highly resistant to acid, which means that chipping of the chrome can be ruled out.

Thermal paste and thermal pads

The included thermal paste is Alphacool's Subzero, with a thermal conductivity of 16 W/mK. This electrically non-conductive paste is particularly well suited for high contact pressures, but Alphacool says it can still be perfectly applied due to its viscosity of 850000 TF. For the thermal pads, Alphacool uses soft pads that fit perfectly to the components to be cooled and are, by its account, very durable. The 2 mm and 3 mm thick pads have a thermal conductivity of 3 W/mK, and the 1 mm thick pads can dissipate 7 W/mK of heat.

Discreet appearance

The matte carbon finish gives the cooler what Alphacool calls a noble appearance. That makes it additionally interesting, Alphacool adds, for private users who want to do without aRGB lighting.

What the loop needs

The block has two G1/4 threads, both at the back. Each takes one of the compression fittings for your tube size, which are not in the box. Thermal pads, thermal grease, a putty tool, screws, EVA washers and the PCI bracket come with the block.

Technical data cooler

Technical data backplate

In the box

• 4x 8x8x1mm Pad
• 2x 84x8x1mm Pad
• 1x 15x15x1mm Pad
• 2x 105x8x1mm Pad
• 2x 50x15x1mm Pad
• 1x 40x15x1mm Pad
• 1x 45x45x3mm Pad
• 1x 15x15x3mm Pad
• 1x 8x40x3mm Pad
• 2x 8x51x3mm Pad
• 2x 8x100x3mm Pad
• 5x M2x5 screws
• 5x EVA washers
• 1x M2x5 screw
• 5x M2x11 screws
• 1x PCI bracket
• 1x Thermal grease
• 1x Putty tool

Alphacool's manual and datasheet (EN) are both PDFs. Its 3D model of the block is an STP file, and the 3D viewer shows it from every side.