Dual RTX 6000 Pro Blackwell Workstation

[theogravity]

I have zero experience with watercooling; I'd like to utilize water blocks for two RTX 6000 Blackwell Workstation GPUs (max power is 600W ea). The case I'm using is a Fractal Design Define 7 XL using an Asrock WRX90 motherboard EEB form factor, measuring 12.0 inches x 13.0 inches (30.5 cm x 33.0 cm).

Possible Radiator placements

• Front fan
  4 x 120 mm or 3 x 140 mm
• Top fan
  4 x 120 mm or 3 x 140 mm

I currently have a CPU AIO for the top with the fans exhausting out, and am thinking of using the front for a radiator for the GPUs.

- I've noticed that Alphacool has 1 and 1.5 slot blocks for the GPUs; I'm assuming there's more cooling capacity for the 1.5 compared to the 1?
- Would it be better to have the fan configuration as exhaust or intake for the radiator?
- What would be a good starting point in terms of the components required to set up a loop? Assume a $1 - 2k USD budget.

My goal is to reduce temps and not having to ramp my case / AIO fans (Noctua) to the point of sounding like a jet engine if possible. The current problem I'm having is that the bottom GPU exhausts into the upper GPU; and the upper GPU exhaust carries to the CPU AIO lines, causing the system to work harder to exhaust.

Pictures of the current build is here:

Threadripper Pro 9965WX AI PC by personalife - GeForce RTX 5080, 2 x RTX PRO 6000 Blackwell, Fractal Design Define 7 XL ATX Full Tower - PCPartPicker

Threadripper Pro 9965WX AI PC by personalife - GeForce RTX 5080, 2 x RTX PRO 6000 Blackwell, Fractal Design Define 7 XL ATX Full Tower

pcpartpicker.com

I do have a 5080 as a 3rd card, but that's mainly for general desktop application use and does not drive that card hard enough to spin the fans.

 

[Eddy]

- I've noticed that Alphacool has 1 and 1.5 slot blocks for the GPUs; I'm assuming there's more cooling capacity for the 1.5 compared to the 1?

The single-slot water block is not compatible with your graphics card; only the 1.5-slot water block will fit. Please be careful, as there are three different RTX Pro 6000 Blackwell graphics cards, each requiring a different water block.

- Would it be better to have the fan configuration as exhaust or intake for the radiator?

The fan configuration shown in the linked pictures of your system is perfect. I would not change it.

- What would be a good starting point in terms of the components required to set up a loop? Assume a $1 - 2k USD budget.

For two 600 W graphics cards, I would use more than just one radiator. After all, we are talking about 1,200 W of heat output, which is more than some space heaters produce. However, since the case does not have room for any additional radiators and is not exactly ideal for water cooling, you will probably have to stick with a single radiator.

If you want to keep things simple and do not care about the appearance, you will not need that many components. Honestly, I would remove the AIO and convert the entire system to a custom water-cooling loop.

I have put together a sample shopping cart for you. It includes two more fittings than you will actually need. However, it is often difficult to know in advance where a straight fitting will work best and where an angled fitting will be more suitable. I would therefore order the two extra fittings as well.

https://shop.alphacool.com/AtsdCartSave/load/key/1ec830f4246303eeacea4ab144b4a5d0