Quad-Slot NVIDIA GeForce RTX 5090 Prototype Appears, Features Three-Fan Stair-Step Configuration

[AleksandarK]

NVIDIA has unveiled a radical graphics card prototype that never reached production, offering insight into its design process. In a YouTube video called "Designing the Founders Edition | GeForce RTX 5090", NVIDIA showcases an unreleased design that would have occupied four PCIe slots, featuring a "three-thirds flow-through" cooling system with an unconventional three-fan stair-step configuration. NVIDIA ultimately rejected the quad-slot concept as impractical for most computer systems.
Engineers refined the cooling approach for the RTX 50-series, developing a more streamlined "two-thirds flow-through" design that maintains thermal performance while reducing the card's footprint to two PCIe slots.

Technical challenges emerged during development, particularly in connector design. The team struggled to create a ribbon cable supporting high-bandwidth UHBR20 DisplayPort 2.1b and HDMI 2.1b connections. Their solution involved infusing glass fibers into the cable, enabling support for three DisplayPort and one HDMI connector. Critical engineering focus was placed on the liquid metal thermal interface material. Extensive stress testing ensured reliability across various orientations, with particular attention to preventing oxidation. Given the electrically conductive nature of liquid metal, an air-tight seal around the GPU die became crucial to prevent potential hardware failure.

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[Vayra86]

They're really REALLY trying to make us believe this enterprise leftover chip is something special don't they? Every time they release one. Lmao. We've had how many deep dives on their FE coolers now?

Next they're going to explain to us how they invented wheels that are perfect circles.

 

[Legacy-ZA]

I am very interested to see how this will impact CPU temperatures if you don't run water cooling, then for the RAM and M.2 drives.

 

[Scrizz]

That first picture looks like the 4090ti that never materialized. You can tell by the design language it's not RTX 3000 or RTX 5000 series. The RTX 4000 series had that concaveness to the outside edges. The 3000 series was flat on the edges. The 5000 series is flat on the edges too, but it also has the smooth middle part and no exposed middle heatsink.

 

[Vya Domus]

Why would they say this was a 5090 when we already know this was a 4090 porotype lol.

 

[Ruru]

Why would they say this was a 5090 when we already know this was a 4090 porotype lol.

Maybe they just recycled the design.

 

[Rubinhood]

What I don't get is: with the growing thickness of the card - now 3 onto 4 slots -, why wouldn't they vent the hot air straight out the case, above the DP / HDMI connectors? Instead of increasingly dumping it onto the processor? "Yes we're doubling the heat around your CPU, but that's OK because that's no longer a GPU problem."

 

[Kohl Baas]

Why would they say this was a 5090 when we already know this was a 4090 porotype lol.

I think what they say is this was the design prototype of the RTX 5090. Yes, the chip underneath was a 4090 bot the cooler itself paved the road for the new FE cards.

 

[Sabotaged_Enigma]

Graphics brick. That's how it should've been called.

 

[Darmok N Jalad]

Someone should caution them on the harsh bending of those 16pin cables.

 

[AusWolf]

The turbulence generated by those overlapping fans... ouch! No wonder they ditched the design.

 

[TheinsanegamerN]

What I don't get is: with the growing thickness of the card - now 3 onto 4 slots -, why wouldn't they vent the hot air straight out the case, above the DP / HDMI connectors? Instead of increasingly dumping it onto the processor? "Yes we're doubling the heat around your CPU, but that's OK because that's no longer a GPU problem."

View attachment 381126

Because to do so you cant have the fan closest to the ports. We HAD coolers like that, they were blowers, and they sucked rocks.

Just put some proper ventilation in your PC already LMFAO. It's not that hard to keep a CPU cool these days.....

 

[TheDeeGee]

What I don't get is: with the growing thickness of the card - now 3 onto 4 slots -, why wouldn't they vent the hot air straight out the case, above the DP / HDMI connectors? Instead of increasingly dumping it onto the processor? "Yes we're doubling the heat around your CPU, but that's OK because that's no longer a GPU problem."

View attachment 381126

Maybe because you can't efficiently (let alone quietly) push 600 Watts of heat through a gap the size of half a cigarette pack?

 

[Darmok N Jalad]

Maybe because you can't efficiently (let alone quietly) push 600 Watts of heat through a gap the size of half a cigarette pack?

This is why I think they need to revisit the form factor for modern hardware. CPUs and GPUs need massive coolers, and we’re installing them in an ATX spec that dates back to when neither component needed active cooling at all. I can think of a few ways they could engineer new designs (and even keep existing port connections), start at the high end and work down. It could even be an entirely new market where folks don’t mind spending big money anyway. Basically, the motherboard should be CPU on one side, PCIe on the other, and mount it horizontally so the GPU and CPU each get their own air channel. Or, they could do something like the 5,1 Mac Pro design. It just seems like something big needs to change, not just for heat, but for structural integrity.

 

[vantila]

What I don't get is: with the growing thickness of the card - now 3 onto 4 slots -, why wouldn't they vent the hot air straight out the case, above the DP / HDMI connectors? Instead of increasingly dumping it onto the processor? "Yes we're doubling the heat around your CPU, but that's OK because that's no longer a GPU problem."

View attachment 381126

It is reasonable to assume that someone running this card might also have a good 3 slot AIO liquid cooler for the cpu. Ideally I wish GPU AIO was as easy to swap in/out as CPU coolers.

 

[InVasMani]

First picture doesn't align with the diagram and the diagram makes you wonder why not have the waste heat more towards the rear in the first place and pulling air more from the front where it comes in from the front of PC case?

 

[trsttte]

I am very interested to see how this will impact CPU temperatures if you don't run water cooling, then for the RAM and M.2 drives.

This was tested with the original 3090 and it improved things, granted that also had the blower part instead of sending everything upwards but the situation will probably be similar. After the air goes through a heatsink it's still cold relatively speaking, for components like ram and m.2 will probably help a bunch since they usually have little airflow to speak off.