Bykski GPU Water Block and Backplate For ASUS ROG Astral Gaming GeForce RTX 5090 32GB OC (N-AS5090ASTRAL-X-V2)

Bykski GPU Water Block and Backplate For ASUS ROG Astral Gaming GeForce RTX 5090 32GB OC (N-AS5090ASTRAL-X-V2)
Includes CNC backplate
In this gallery — tap to open full size
N-AS5090ASTRAL-X-V2 Pre-order
$263.99$290.99USDFree shipping, lower 48

US import duties and tariffs are included in every price.

Ships directly from our Idaho inventory. You avoid overseas sellers, processing delays, international shipping, customs hold-ups and additional fees.
Pre-order — normally stocked
Expect dispatch in about 20 business days
Latest 24 business days. Cancel any time before it ships for a full refund.
A regular catalog item — we're between shipments. Your order is filled before any stock goes back on the website.
Fits these 8 boards, and only these

This part is machined for the 8 boards listed below — nothing else. Board revisions and partner designs differ, so match your exact model against the list before you order.

  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB OC
Not sure? Send us your model/part number and we'll confirm it for you.
Not ready to pre-order?
Fittings for this block

PrimoChill SX fittings for the G1/4 ports, in stock in Boise. Pick a finish and how many you need; 6+ in any mix and the price drops.

Pick a finish, then add quantities.
Building your first loop? Plan the rest of it
Why buy it here
US warranty, handled in Boise
Claims are settled here, by the people who sold it to you.
Custom watercooling since 2002
PrimoChill, from Boise, Idaho.

About this part

The Bykski N-AS5090ASTRAL-X-V2 is a full-cover GPU water block with a matching aluminum backplate, made for PC builders adding a flagship graphics card to a custom liquid cooling loop. It fits the ASUS ROG Astral Gaming GeForce RTX 5090 32GB OC and the other cards it fits.

One nickel-plated copper cold plate draws heat from the GPU chip, the memory and the power stages at the same time, so your loop's radiators carry the heat of the whole card. A grid of 56 micro-channels spreads that heat over a wide area, which helps hold temperatures steady through long gaming or rendering sessions. With the stock fans gone, the card also runs much quieter.

In the box
  • GPU water block with backplate: 1
  • 1.5 mm thermal pads
  • Thermal paste: 1
  • Backplate screw
If the gallery shows a parts diagram, that diagram is the source of truth for what ships.
Datasheet
Technical specifications 14 specs
Cold Plate MaterialNickel-plated T2 copper
Top MaterialAcrylic
Backplate MaterialAluminum
Plating Thickness0.001 mm - 0.002 mm electroless nickel
Cold Plate Thickness8.5 mm
Base Thickness Under Channels0.35 mm
Copper Plate Length159.85 mm
Micro-Channel Width0.3 mm
Micro-Channel Count56
Micro-Channel Surface Area14,393.42 mm2
Water Block Dimensions260.78 x 162.7 x 26.57 mm
Port ThreadG1/4
Lighting5V ARGB, 3-pin header
Warranty1 year

What buyers said

Left by people who bought this part here. Compatibility reports are the useful ones — if you installed it, say which board.

Customer Reviews

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What installing it actually involves

Three steps, in the order that matters. The one people get wrong is the first.

01
Confirm the hardware

This block fits 8 boards:

  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB OC

Match your exact model — not the family.

02
Mount it dry

Thermal interface material as supplied. Even mounting pressure, correct bracket orientation, no over-torquing.

03
Leak test before power

Run the pump on a bench supply with the rest of the system unpowered. 24 hours is the standard, an hour is the minimum.

Custom water cooling is installed by you, at your own risk. We are not responsible for leaks, or for damage to your parts or system. If you're unsure at any step, ask before you power the loop.

Questions people ask about this part

Answers specific to N-AS5090ASTRAL-X-V2. If yours isn't here, ask — we'd rather talk you out of the wrong part than sell you one.

What does this part fit?

It is machined for 8 boards:

  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090D 32GB OC
  • ASUS NVIDIA 5090 - ROG ASTRAL GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB
  • ASUS NVIDIA 5090 - ROG ASTRAL LC GAMING GEFORCE RTX 5090 32GB OC

These are machined to a specific hardware layout, so match your exact model rather than the family before ordering. Part number N-AS5090ASTRAL-X-V2.

Is it in stock, and when will it ship?
It is a normally stocked item currently on pre-order — we are between shipments. Orders dispatch from Boise, Idaho within 20 business days, and pre-orders are filled before any stock goes back on the website.
Can I cancel my pre-order?
Yes. A pre-order can be canceled any time before it ships, for a full refund. Nothing is committed until it leaves Boise.
Will I pay import duties or customs charges on delivery?
Not on a US order. US import duties and tariffs are already included in the price, so nothing is collected at the door and there is no brokerage fee. Orders shipped outside the US may owe that country's customs fees and duties.
Who handles the warranty?
PrimoChill, from Boise, Idaho. Every claim is handled directly by our support team rather than returned to an overseas factory. Installation is at your own risk: we are not responsible for leaks or damage to other hardware.
Is shipping free?
Yes — shipping is included at this price for addresses in the lower 48 US states.
Are printed instructions included?
No printed manual is included. Installation references are in the product gallery images, and the install guides on this site cover the process step by step.
Do I need anything else to use it?
A water block is one component of a loop: you also need a pump, a radiator, fittings, tubing and coolant. If you are starting from nothing, an AIO or a distro-plate kit is the shorter route — ask and we will spec it.

Ask us before you order

Send your exact hardware model and we'll confirm the right part before you spend $263.99 — or tell you honestly that this isn't the one.

Returns are accepted within 30 days and are easy to start in the support center. Unopened items can be returned for store credit with no restocking fee; other returns carry a restocking fee, higher for items that have been installed or used.

Ask about compatibility