If you've decided that money is no object and, the unknown be damned, you're buying two GeForce RTX 2080 Ti or GeForce RTX 2080 graphics cards, you now have an assortment of NVLink bridges to choose from.
Whether you should actually do that or not, we can't really say until we know how these cards handle real-time ray tracing beyond the limited number of demos we've seen to date. It's an expensive gamble at the moment. Nevertheless, the hardware is available, for those who have both the inclination and requisite disposable income.
You'll need an NVLink bridge to connect two RTX cards together. Nvidia will happily sell you one for $79.99, though if you're looking for something spicier (read: gaudier), there are custom options available.
The one from EVGA looks like something Batman might yank from his utility belt in a pinch. It features pockets of RGB lighting, which you can customize through the company's Precision X1 software. It runs $89.99 and is available now.
If you're not into that design, here's a look at Gigabyte's NVLink:
Like EVGA's variant, Gigabyte's Aorus NVLink supports customizable RGB lighting. Users can cycle through various lighting effects. This one is not yet available to purchase though.
Finally, here's the custom NVLink that Asus came up with:
Like the rest, it supports RGB lighting, with glowing ROG logo. It's a more block-shaped the other two, not including the angled cutouts.
All of these NVLink bridges come in 3-slot and 4-slot models, with the actual connectors spaced appropriated for different size graphics cards.
What about the GeForce RTX 2070? That card is slated to arrive on October 17, though everything we've seen so far indicates it will not support NVLink. So, for a dual RTX setup with NVLink, you're looking at least two grand for just the cards (and realistically more, based on current prices), plus another $80 to $90 for the NVLink.