What's better than ONE GeForce RTX 5090?

PC Building
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Shhh… don’t tell anybody but the project that ArsenalPC’s manager Doug has been working on for the past several months is finally coming to fruition!

dual5090
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Getting two GeForce RTX 5090 graphics cards to fit into a single PC was more of a challenge than initially expected! Some of the things we dealt with included:

  • While all aftermarket designed RTX 5090 cards advertise themselves as triple-slot, the cooling shroud extends into the fourth slot on every single one.
  • Ensuring there were sufficient expansion slots represented by slot covers on the back of the case, so that the bottom 5090 could be mounted properly.
  • Ensuring there was clearance not only between the cards, but underneath the second card within the case, so there would be sufficient airflow.
  • Making sure the motherboard had a PCIe x16 slot in the correct position for the second card.
  • Making sure the power supply was sufficient to run dual RTX 5090 cards without having to limit their power - after all, what would be the point in using these behemoth cards with a power limit?
  • Making sure there was overall enough airflow in the case to handle 1200W of GPU heat on top of the other components.

In the end, we settled on a Fractal Design Meshify 2 XL which gave ample clearance for the two cards mounted to a Gigabyte X870E Aorus Elite Wifi7 with an AMD Ryzen 9 9950X (not the 3D V-Cache version, as the target customer for this type of PC will value higher clocks over 3D cache). We’re also using 256GB Crucial Pro DDR5 RAM in a 4x 64GB configuration. Powering the system is a Cooler Master 1600 V2 Platinum power supply, which features dual native 600W PCIe5.0 cables so as to ensure full power to both cards.

A single RTX 5090 is capable of processing 3352 AI TOPS.
Two of them would theoretically be capable of processing 6704 AI TOPS.
For comparison, NVIDIA’s own RTX Pro A6000 Blackwell is capable of 4000 AI TOPS with a singular card, which costs approximately $12,000 alone for just the GPU. We haven’t finalized pricing yet, but there’s a strong chance this PC will sell for less than a typical system featuring just one RTX Pro A6000 Blackwell, while providing about 67% more AI TOPS…

Final testing is still under way, but you can look forward to finding this system for sale in the next few weeks on our Newegg store page!

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Did you think about putting both of those cards into a custom water cooling loop? I feel that would have fixed all of the spacing issues. I also do not know much about water cooling.

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Keep this one on the down low… but yes, we are actively considering hardline tubing custom water cooling solutions for some of our gaming PC configurations. However we do not have plans to offer that for any of our AI workstation builds at this time. This may change in the future, but we’re pretty sure our workstation customers don’t want to perform maintenance on a custom water cooling setup every 6 to 12 months.

Furthermore, shipping a system with a custom water cooling system requires for it to ship empty of any liquid - and the customer has to add coolant upon arrival. These are additional steps that a top-tier gaming enthusiast will be excited to perform, but would have the opposite effect on someone looking for an ultra-powerful workstation - they just want to plug and play!

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This is craaaazy! Fitting 2 RTX 5090 GPU’s in a single PC!

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what size of a model can be run on a unit like that? what would be the applications? Not that I would ever even begin to know how to use it, but just curious.

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As far as we understand, AI models can basically take advantage of as much GPU power as you can throw at it. That’s why, for example, Intel’s new Arc Pro cards are available in dual-GPU form from Maxsun overseas - the type of models that could benefit from larger VRAM buffers can simply utilize extra VRAM on more cards.

Based on what we’ve read online, 48GB is a kind of “sweet spot” for running AI models at this point. NVIDIA has priced that WAY out of the market, intentionally leaving the only single-card option as the RTX Pro A6000 Blackwell which costs about $12K street pricing. Granted, that has 96GB VRAM… but if you’re ok with settling for “only 64GB” then a dual-5090 setup will blow it out of the water, with 67% more actual compute power than a single Pro A6000 Blackwell.

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