How to mount dual RTX 4090s on a ASUS WRX90E-SAGE?

I am building a machine learning server on a WRX90E-SAGE motherboard, with dual Gigabyte OC RTX 4090s, which I want to go in the green marked PCIe slots in the image below. I am using a Fractal Meshify 2XL case.

But the instructions for the GPU anti-sag mounting brackets are assuming that there is a single GPU, and there is no way to mount two of them.

The instructions also are assuming the mount points for an ATX motherboard as opposed to the EEB motherboard. The two bottom right screws (circled red in photo) which the instructions say is where to install the mount bracket, are in a different location from the standard ATX board position. So even if I put in a mounting bracket for the top card, it likely won’t be in the right place. …

I’m not sure what to do here, short of 3D printing my own custom brackets. I’m wondering if anyone here happens to have mounted dual 4090s on this board, and how you did it?

I think you should either consider a rackmounted case or add an anti-sag bracket to the bottom one and some kind of item between the two gpus gap

some options:

vertical mount? would two fit in the case vertically? fractal do a mount for that case, but doesn’t look like two of their mounts would fit, but maybe there are otehr aftermarket vertical mounts. here is the fractal one for reference

there are also aftermarket anti sag mounts e.g. this one is quite tidy

I have considered vertical mounting but unfortunately I think I can only vertically mount one of them because of the way my case is designed (there are only enough vertical slots/knockouts for one of the cards), and with other components (HDD trays, etc) …

I’m honestly just thinking about going the janky DIY route at this point and jamming an item (lego? eraser?) between the two GPUs and then using one of these to prop up the bottom one.

Are these sorts of anti-sag braces legit? Should I maybe get 2 since the bottom card would also be supporting any weight from the upper card sagging? Maybe one under each corner on the right-side of the bottom card?

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… well, I actually ended up going with this one from Antec (even though I hate flashy rainbow RGB) because it was the only one I could find with good ratings that was made for supporting dual GPUs. And I can just leave the RGB disconnected, if I can’t manage to control it from Linux.

I’ll post back later with updates about how it works :slight_smile:

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Put the whole it on a side? Or get a 4090 with AIO, they weight a bit less.

The Antec brace didn’t work either, because the braces were too thick to fit between the upper and lower GPU, and the minimum height of the bottom brace wasn’t low enough and was putting upwards strain on the bottom GPU.

I ended up returning it, and going with a cheap DIY solution: I used a $9 screw style brace under the corner of the bottom GPU, and then stuffed a piece of an old toothbrush handle wrapped in electrical tape between the upper and lower GPUS to brace the top one :toothbrush::rofl: :toothbrush:

less jank?

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Nope, I actually bought and returned that exact brace, because the upper one wouldn’t fit in between the upper and lower cards at any of the angles that it was possible to position it. It might have worked if I had another 2 or 3 inches of space to back it up towards the front panel, but the 4090s are so close to the front panel that there wasn’t really room to position the brace further back. Anyways, my brace + toothbrush handle solution is working fine, and eventually I’ll just 3D print a little piece that looks nicer, to replace the toothbrush.